Is one of the cabinets exactly 24" or 18"? Those are the two standard DW sizes.

I haven’t had a chance to measure it yet, but I’m almost positive the second one from the sink is “24!
Would I need to cut into the cabinet with a saw to make space for the dishwasher, or do I need to remove the cabinets entirely?

If you could remove a 24" cabinet entirely, that would be preferable, It's really going to depend upon how the cabinets are constructed and how the individual cabinets are combined.

Ideally it would be the cabinet immediately adjacent to the sink, for plumbing purposes.

Do you own a multitool? Jig saw? Bigger voltage cordless drill? Can you sweat copper? Bond PVC? Remove the rats nest of stuff under the sink and put in a new drain, lower down, so you can have a disposal, and the DW can drain into it? Have you added a new outlet by daisy chaining from another? Does your panel have space for a new dedicated circuit? Do you understand where the mains cutoff is to be able to attach wire to a breaker in the panel? Can you crawl around in the attic to run that wire from the panel to behind the sink? Drilling through all the wood in the way, in a way that doesn't weaken that wood. Can you cut through wood with a multi tool or jig saw and achieve a laser straight line? Can you stain and finish raw wood to match the existing?

You can probably get there, and do all of that. Anyone with a handy knack can. Over time. But you have to crawl before you walk. Pick any one of the things involved in doing this job to learn more about and practice. Maybe get some deeper understanding of Electrical first, as it is the one that intimidates most people. Pick the scariest and hardest, and the rest will be easier in comparison to start to learn about.

The best solution is to completely remove a 24" cabinet. Typically, cabinet side stiles are screwed together, unscrew those. The cabinet top may be screwed into wall studding along its top edge. Unscrew those, or tear the cabinet apart to get them out. The counter top is likely only held to the cabinet by silicone caulking, break that loose. You'll need a 120v romex cable run into the cabinet area. I then mount a wall receptacle and pigtail the dishwasher with an appliance cord/plug. The drain can be run through the back side of the cabinets to the undersink area and drained there..

If the cabinet is on the end of counter run, you will need to provide support for the counter on the end of the run. The DW itself isn't the support.

@User: "Do you own a multitool? Jig saw? Bigger voltage cordless drill? Can you sweat copper? Bond PVC?..."

This is ridiculous. Nobody needs to be able to "sweat copper" or "bond PVC" to install a dishwasher.

"Drilling through all the wood in the way, in a way that doesn't weaken that wood. Can you cut through wood with a multi tool or jig saw and achieve a laser straight line?..."

Oh come on. You have no idea how the cabinets are built. If separate cabinets are fastened together side-by-side may be possible to simply disconnect one cabinet from the rest, break the glue bead between the cabinet and the countertop, and pull it out.

"Have you added a new outlet by daisy chaining from another? Does your panel have space for a new dedicated circuit?"

How do you know a new outlet is necessary? There may be one under the sink she can plug the dishwasher cord into.

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@User: "You will need to run a new electrical line and redo plumbing as well as alter cabinetry."

Wow! She'd have to change the hot-water line valve.

There may be an electrical outlet under the sink. You don't know.

You have no idea whether she would need to "alter cabinetry".

Those are old built in place cabinets. There would be no reason to have a dedicated electrical outlet under the sink in an old installation like that. All of the drain system has to be redone, and yes, the hot water supply. If you think a saddle valve is the answer to that issue, then you have never dealt with the number of leaks that they cause. On an installation that old, she will be lucky if there are even fixture shutoff valves at any of the plumbing anywhere. Don't minimize the amount of work that this is. It is doable. By a handy experienced homeowner. Just not by a complete novice.

@User: You simply have no basis for any of those statements. You know nothing about the age of the cabinets, the existence of an electrical outlet, the water supply, shutoff valves, or anything else. None.

When I was a kid my family had a portable dishwasher. It was on casters, sat up against the wall until ready for use, then roll it over by the sink and attach to the faucet with an adapter that screwed onto the faucet aerator. Worked fine, and I later used it in an apartment as a young adult.

Could be another option here, if the installation is a barrier to having a dishwahser.

This kitchen is a recent remodel. The cabinets are basic builder grade, but I have yet to take a lol at the plumbing and electrical situation under the sink. This kitchen itself was a newer addition to the home, so it’s pretty up-to-date. I did take a look at the cabinets today, and there is a visible seam between the 24” cabinet right next to the sink and 48” doors next to the wall, so I think I could remove both sets of cabinets and install a dish’s washer and new set next to that. Does that make sense?

@HU-867564120: "A home of that age has a 60 amp panel that is full, and likely overflowing."

It has an electric stove which typically requires a 50 amp 240 volt circuit. How could it have a "60 amp panel that is full, and likely overflowing"?

"It won’t be a dedicated circuit that is required for a DW."

A basic Whirlpool dishwasher just requires a 15-20 amp 120 volt outlet.

"not including that $900 GE DW"

The Whirlpool 24-in Built-In Dishwasher in Biscuit color (to match the range) is $530.

There's a lot we don't know here. We considered the same project for our home with 1939 built-in-place cabinets, though ultimately ended up renovating the whole kitchen. But a lot of the work we did was the same. In our case, we had a single-story house with an accessible basement below, so it wasn't that complex to wire and plumb for the dishwasher. Ours is plumbed to cold water, and we just hired a plumber to run a new line alongside the faucet line and an electrician to wire an outlet; I think the permit cost more than the actual work! Our old cabinets had no backs--just built against the wall--so that was actually even easier than with the new cabinets, where we cut out the back to have access to a new outlet and new shutoffs for our faucet [we have a wall-hung faucet with pipes in the wall]. What was tricky for us--and the main reason we decided to renovate--was that the cabinet next to the sink was 21"--not big enough for a 24" dishwasher but would have needed a lot of filler for an 18" dishwasher (which we almost pulled the trigger on). Because of our layout--at the time we had an internal chimney on the other side--we could only put it on one side of the sink.

I will say that we had already updated the electrical for the house, so had plenty of capacity for the dishwasher. If you have older electrical, that can be a barrier. No way to know here whether the existing electrical system has room. (FWIW, our neighbor is just now upgrading from a 60a main panel in order to go solar; his old panel handled his permitted kitchen remodel with no issue. That will depend a lot on the size of the house and the other demands on your electrical system, though.)

OP, a good first step here would be to have an electrician and plumber out to take a look and give you a sense of how involved the work to add the needed lines might be. That will give you a sense of how DIY (or not) the project will be. I'd also measure that cabinet to the right of the sink and see if it will fit either an 18" or 24" dishwasher; it is worth it to go 18" if it means you only have to touch one cabinet, because once you touch two you start to get into a much bigger project. Good luck!

They may have been purchased used, but the seller of the home was a flipper, and these were recently added to the home - within the last 10 years at most. I’m going to take an entire end section out to rearrange some things.

"I did take a look at the cabinets today, and there is a visible seam between the 24” cabinet right next to the sink and 48” doors next to the wall"

Please measure with a tape each cabinet flanking to the left and right of the sink cabinet. Even from the internet pic with skewing perspective, when comparing door panel sizes against known sizes (30" stove, 33" or 36" sink), the cabinet to the left of the sink looks 24", to the right looks 18".

To the left, if it's a 24" cabinet, as Buehl said you need another 3/4" end panel space to support the counter. If you could muster that, it would be a relatively simple swap.

Since these are all box-unit cabinets that you cannot alter if it changes the door panel size, you cannot cut say 18" out of a 48" cabinet. It could be feasible to take 24" out of 48", but not unless you are a seasoned DIYer. So on the right, it depends on the cabinet sizes (18" + 48"?). It also might be possible to find matching cabinets off-the-shelf and replace them for different sizes.

A few replies have referenced the 18" cabinet but it's not clear if they're recommending an 18" dishwasher. Don't do that. They're specialty appliances, limited choices, and comparatively expensive to standard 24" dishwashers.

"I did take a look at the cabinets today, and there is a visible seam between the 24” cabinet right next to the sink and 48” doors next to the wall, so I think I could remove both sets of cabinets and install a dish’s washer and new set next to that. Does that make sense?"

It doesn't make sense to me if the replacement cabinet wouldn't match the existing cabinets making the kitchen look worse than it does now. If possible, I would remove only the 24" cabinet to the right of the sink cabinet. Before doing anything, I'd check for an electrical outlet under the sink you could use for the dishwasher. If there is none, I'd determine how a new circuit could be added.*

• How To Install A Dishwasher Made Easy!
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*You could add it under the sink or inside the dishwasher cutout. If you do the latter, it must be placed in the proper location per the installation instructions (example). It would be easier to put it under the sink.

Removing a 24" cabinet adjacent a sink cabinet to install a dishwasher is a job for an intermediate level do-it-yourselfer. Those look like modern cabinets that are ganged together.

In 1973 we bought a newly remodeled Victorian and immediately had dishwashers added to the kitchens in both flats. The contractor, probably not licensed, removed the cabinets by unbolting them from their neighbors and inserted the dishwashers. When the dishwashers needed replacing, we had a licensed contractor who upgraded the electricity and added a separate circuit for each dishwasher. However, the newer dishwashers wouldn't fit into the space, possibly because of added layers of flooring (I can't remember), so we had to have new countertops laid over 3/4" plywood.

First, measure the dimensions of the cabinet space where you intend to install the dishwasher. Ensure that it is wide enough, tall enough, and deep enough to accommodate the dishwasher. Select a dishwasher that fits within the measured space. Consider the type (built-in, portable, drawer), size, and features that best suit your needs. You'll need several tools like a screwdriver, adjustable wrench, drill, level, tape measure, brackets, screws, electrical connectors, water supply line, and drain hose.

Remove the cabinet doors and shelves to create an open space for the dishwasher. If there is a false drawer front covering the area, remove it as well. You'll need to extend the existing water supply and drainage lines to the dishwasher location.