What's behind the door? Use some pretty baskets with lids to contain your items under the sink. Put up a narrow shelf on the wall with the niche for some of your items. Put them in pretty containers. Maybe use a hanging pocket storage thing over the door on the inside. Maybe attach a curtain to cover the space under the sink if you don't want anything to show.

I would not let it bother you. Eventually you can replace it.

As Tara above mentions look into containers. Are you near The Container Store?

If you can afford to replace the vanity of course get one with doors, and a medicine cabinet would help too. They're better if recessed, but if you can't do that you can buy ones that don't have to be recessed. Just make sure you install it high enough to not bump your faucet when the door is open. Baskets for the open part are certainly an attractive interim solution.

Short term: tension rod with a café curtain on it to hide what's below the sink. (We have a cabinet where the lower section once hid plumbing, so it doesn't have a door, and that has worked well over the years until we finally get around to adding doors.) Long term: replace this with a closed vanity, and get a recessed medicine cabinet for the wall.

Also be ruthless and only the items you use daily get special real estate under the vanity. everything else is in the linen closet. if you do your makeup and skincare, get a desk height vanity (can be cheap ikea with lots of drawers) and cute chair and find dedicated space with proper lighting outside of the wet and humid bathroom for that. looks like a really nice space!

More pics of the space. I see a bit of a wall where maybe you can put some shelves. And what is behind that door????? Try to arrange your everyday items in baskets for when you use them - daytime cleanser, lotions, and quick makeup; dental; nighttime facial products. That way, you grab one basket, everything is in it, and then you put it back instead of having to go to 4 different places for the 4 products you use every night. And why do you need Dawn dish detergent and a stainless steel bowl on your vanity???

Purge, add a shelf, buy matching baskets. The baskets will hide the clutter.

Simplistic option would be adding shelf and baskets as M Riz suggested. Link to an inspiration pic.

https://www.houzz.com/photos/bathroom-scw-interiors-photos-by-gridley-graves-traditional-bathroom-dc-metro-phvw-vp~27117534

Not sure if adding drawers is possible or feasible but just throwing it out there anyway.

https://www.houzz.com/photos/small-yet-sophisticated-bathroom-remodel-transitional-bathroom-chicago-phvw-vp~55119551

Get rid of 90% of that collection of crapola and you won’t ”need” so much storage. And that’s the big issue that everyone is dancing around.

I have to agree it seems a lot of stuff there tha does not belong in a bathroom but we need a to scale floor plan of the whole space and pics of the whole room. I have to say I am not a lover of baskets for storage you can never find anything in them and IMO look messy I love closed storage too. What is tah space with what looks like a shelf ?

thank you all SO MUCH

the master closet is RIGHT in between the two.....not sure why anyone would do such a thing - which has also led me to a dilemma in regards to getting a nice bath mat? any thoughts? pictures? when i get this overwhelmed my mind just freezes up....i know there's a lot of potential here, i just need to get started in the right direction :(

I'd recommend getting some sort of sliding storage for under the vanities, either sliding shelves, or sliding drawers; something like this is made to fit under a sink and avoid the pipes: https://www.amazon.com/Bextsrack-Organizer-Protective-Bathroom-12-2Wx16-5Dx14-5H-Inch/dp/B09QBV5JGL/ref=sr_1_18?crid=3A7OF7LNUJJCX&keywords=sliding+shelves+for+kitchen+cabinets&qid=1657191828&sprefix=sliding+shelve%2Caps%2C106&sr=8-18, and I have several of these under sinks as well, if the pull out shelves don't fit your situation https://www.amazon.com/Simple-Houseware-Stackable-Sliding-Organizer/dp/B07NSN27K3/ref=sr_1_3?crid=OOGIU8SDXVJQ&keywords=simple+houseware+2+tier+sliding+cabinet+basket+organizer+drawer&qid=1657192013&sprefix=simple+house%2Caps%2C109&sr=8-3 These would help keep it a little tidier looking, and still make it easy for you to get to things. You could use them on top of counters too.

Shelves in arch cove & storage bench.

Yes, the arched space by the closet door is usable storage space. Is it at least 3” deep? If yes, it can be your overflow storage for the stuff under the sinks. I started the Curly Girl Method at the begining of 2020, and so I have nothing negative to say about having way too many different toiletries - lol!

If you or your partner have any carpentry skills at all, you can cut some narrow shelves for the arched space. If you can acurately measure and cut, you could consider insetting shelving strips into the sides and back of the walls to have adjustable shelves where you can move the pegs that hold the shelves. Otherwise, rig up a way to hold your shelves. If you want an easy-peasy DIY front for this new storage, then get a pleated or roll-up shade and hang it above the arch or near the ceiling. I like the push-up pleated shades I have over my patio doors, they are so eacy to use, so I would start there. You could even put a strip of LED lights on a timer behind the shade to fake a window.

Of course, a semi-competent or professional carpenter could do the doors for the cabinets and doors for this new storage in the arched cabinet, as well as install a shelving strip kit. If you are at all DIY, you can order the doors online yourself at one of the cabinet door suppliers and install them yourself. If you add a faux-drawerfront panel above the new doors on your vanities, it will not even be obvious that this was a re-do.

Get some overlay cabinet doors to cover the bottom and add a false drawer front (in the blank space over the opening).

Or, get rid of one vanity and replace with a storage wall.

Replace the other vanity with one that has doors/ drawers. Don't repeat the mistake with these vanities. These are stand alone units; the counter should not intersect the wall. They look goofy with the counter abutting the wall & with the side splashes. Plus leaving you with that narrow hard to clean space.

In the long run, you will be happier with new vanities.Ones with a full bank of drawers on one side, door under the sink. And make it a vanity that goest to the floor/has a toe kick, so you don’t have to vacuum waaaaaaaay in the back corners, which will get gross with hair and skin and powder.

Can you add between-the-studs medicine cabinets on the side walls?

Otherwise, you will be spending the same amount of money and time getting doors made, and still having to add plastic drawer units inside that don’t qite fit so you go buy different ones, Don’t chase after-market solutions, do what you need the first time.

You can get ready made unfinished cabinet doors from Menard's at a reasonable price. If you are lucky & can find a size that will work.

https://www.menards.com/main/kitchen/kitchen-cabinets/cabinet-doors-drawer-fronts/standard-cabinet-doors-drawer-fronts/quality-one-trade-unfinished-maple-square-recessed-panel-kitchen-cabinet-door/sfpd10215-m/p-1486711332754-c-13296.htm