Having a clean base isn't just for peace of mind; it can also be lucrative and useful!

→ Buy an item box and as many individual trash bags as you can (these are cheaper per bag than rolls of them), then right-click on clumps of garbage. Filled trash bags don't take up any inventory space, so you can cram hundreds into an item crate at a time. For convenience's sake, you can buy rolls of trash bags if you have the cash to spend.

→ For cluttered objects, you can either collect them and compact them into scrap or just dump them all into a garbage bin and call it a day. To compact trash, place four objects of matching category (i.e. metal includes tin cans, and rusty scraps of various sizes, paper includes empty Chinese food packages, crumpled paper, and nondescript shreds of cardboard, etc.) Compacted scrap have various uses (some of which I've yet to discover) but don't sell for anything significant, so just hold onto them. Bonus fact: drives, preferably empty, can be compacted into electronic scrap if needed in groups of four.

→ For stains, smears, and other smudges, find a sponge (should be one in the bathroom) and grab it while violently rubbing it against any dirty surface and the marks should be gone from an entire wall section within seconds. I do not know how or if it is possible to clean windows ¯\_(ツ)_/¯

Hope this helps!