paint it, put cheap rugs in, fix a leaky faucet, change some switch plates and replace the crappy drapes.

I did exactly that and the PM lied like a rug, like I knew they would.

I suggest for snow on the ground makes sure you have a rug in the entry to wipe feet and I keep something to wipe up any wet spots.

I once had a older SFR that had old terrazzo floors, needed to be refinished, but didn't have the funds; bought a huge area rug and it rented immediately!!

Eric,    My advise to you/your friend is to actually take a walk through the property, and try to fix the easy stuff, missing door knobs, replace light bulbs, fix the gutters, vacuum the rugs, clean the place, deodorize etc...  

A pattered runner stands alone...like a rug.  

You know - cleaning, installing mini-blinds, pulling up rug, light painting...J

I suppose if you had the right pattern, they could work in a living space without looking overly institutional.In the apartment itself, I would lean towards vinyl plank with an area rug in lieu of carpet ... much easier to clean and deal with between tenants.  

That place was a bit rugged!  

I would ask the tenants upstairs to be aware that their kids running around probably sounds like a herd of elephants to the tenant below and maybe add some throw rugs to the upstairs unit and hope that quiets things down for the downstairs tenant.