@Jared Lane a real French drain would be installed below the height of the basement slab somewhere next to the footing just outside the basement walls. I’ve done at least 1 by hand and it wasn’t all that bad. No problem with the occupants because it’s all exterior. Honestly, you don’t want to do that kind of digging too much with an excavator anyways, and often there’s some decks you have to get under anyways. After I dug it up, I cleaned the walls, rolled water proofing on the walls, then, adhered 6mil plastic to the wall up to the grade and ran it down to the French drain area. When we backfilled, we also solved the slope issue by making sure the grade slipped away from the house for at least 6’ (12’ recommended). Usually the main problem causing water is the grade sloping toward the house, and lack of gutters that run the water away with the proper downspout. As far as walls in the basement, that stuff could cost you some significant time with all your slab drainage corrections etc. watch out for the lawsuits right now on mold etc. people are burning bridges and going for broke and you don’t want the chaos to take itself out on you for mold. Your best quick solution may be to make the basement off limits and lock it, put a dehumidifier in there (there should already be one) and find where the low spot is, bust a hole in the slab the size of a 5 gallon bucket and drop a good sump pump inside the bucket when you get it in the hole.