I painted and put up crown molding in my place. Landlord took a look asked for the receipts and paid me.
I enjoy my place and the labor didn’t bother me. Have an unfinished garage that I am thinking of dry walling and throwing some laminate floor on. She has already offered to pay me if I do it. This is a couple of weekends but if it is done right I can add 250 square feet of living space while keeping rent constant.