Keep existing structure, complete gut the space, new footer(s) inside existing structure, load bearing structure above those, floor joists above that, subfloor and refinishing. Have engineered plans/permits before starting. Basically an insulated and interior crawlspace below the new floor when done. Have access to down there, you could use it for storage also. Not impossible. Plenty of work but not impossible. Sounds like it would need a big reno anyhow from description. Just more work than a standard DIY gut and redo due to structure work involved. This is something a GC and crew normally does. This does give you a chance to make it how you want it. Hopefully selling price reflects the need for a large reno. what unexpected or nasty surprises did you encounter? I have found a lot of things in my current house where I ask myself, what were they thinking? So you will probably find a fair amount of stupid behind the walls. When I redid the drain system, there was an old 1-1/2" drain line from the kitchen that had so much gunk built up there was maybe 1/2" left for actual draining. Also the electrical was mix of grounded and ungrounded wire, and tons of junction boxes in the basement, I redid all that mess. Found a lot of the wire nuts where the wires were loose or arcing was happening and it welded the wires and nuts together, at least they used junction boxes or the house probably would have burned down... In laundry area, an ungrounded range receptacle was used instead of a grounded dryer receptacle even though the wire they used did have a ground. At the panel the fuse was rated at 30A so it was safe, just annoying I had to get a different cord to plug it in when I moved in. I eventually changed out the outlet for future owners... Oh yea that old fuse box the main fuse connection started arcing! Talk about fire hazard! So that was replaced with a breaker panel. Also in the laundry room the washer standpipe was a 2 inch that went into that same 1-1/2" from the kitchen with a vent tee instead of a sanitary tee... (so much fail). It now has its own vent and drain to the soil stack. Higher radon level than wanted, had to add active mitigation. Kinked gas line multiple places... Bath vent in attic went to above a soffit grate so 'some' moisture went outside but some got in attic. Not enough attic ventilation. Lots of other stuff, but cant remember it all lol.

We call those bi-levels here and they are still incredibly popular where I am as new builds - I was surprised when I moved here. These days though they often seem to come with more generous entry areas. I would not move the entry "down", if anything, move it "up" but then be aware: 1. You will have a lot more stairs outside to get in; 2. You will need to change inside floor/stairway a lot to address a staircase to go down the lower level; 3. Reconfiguring stairs is costly; 4. Stairways take up a lot of space (and if you have older stairs, you may expect more space to be taken up due to Code changes since it was built).

Sina is correct regarding basic laminate. Cheap laminate won't hold up. You have to get the better quality. I used a moisture resistant and scratch resistant laminate at my front entry and it is holding up nicely. The upgraded laminate is still cheaper than I high end wood floor. the 5'x5' area that I did cost me around $100. That included the flooring and the transition strips. The flooring already had the padding on it. If you buy flooring without the pad/ backing you will have to buy it separately. I got my flooring at Home Depot on sale at 50% off as it was special order that someone didn't pick up. Shop around for deals and specials like open box or special orders that weren't picked up. If you are a member of Sams, BJs, or Costco, a lot of times I have found clearance laminate deals.

Hi We have a walk-in shower with sliding door and a fixed panel and the threshold is unique which was installed by new build buider some 6 years ago. The shower frame, sliding door and fixed glass panel do not have any manufacturer / brand name so looking for some advise who might know the manufacturer or this particular threshold part supplier. We have similar threshold in other shower rooms, so I know this threshold piece comes in length and can be cut to size. See photos below of threshold. RIGHT SIDE LEFT SIDE FULL LENTH, Threshold lifted up as silicon is now loose. you can see that it has a built-in plastic seal which is coming off from the threshold. You can also see both ends of thresholds in this photo which is unique. google search could not find any threshold with this type.