I doubt that you will get 10:1 price increase to cost of materials, but no doubt you will get more than you put in, even if you paid yourself fair labor. A neat and well-cared-for unit will sell faster and for more money every time.
Not long ago, my mother passed away. First off, my mother was a heavy smoker. She lived in this condo for 17 years. Rarely opened the windows and smoked for about 15 of those years. The walls were painted, but the doors and trim, never. It needs to be painted badly. The odors are pretty much gone however. I had the carpets and upholstery cleaned after she stopped smoking. All the window treatments were replaced. She had the walls painted, light pink in almost every room. The painter was an amateur and it looks bad.
I say clean and paint the trim back to white. Paint the walls off white, with only the slightest touch of color.
The entire place is carpeted. The carpet is extremely worn out. I say replace the carpet with mid-upper grade laminate floor for the living room, dining area and hallway. Something with a little texture and depth. Not the 99￠ a sf junk. The bathrooms, do in vinyl tile. There are vinyl tiles that look like stone and even have edges where you can put a little grout in them at Home Depot. The kitchen has relatively new carpet in it and the 2nd bedroom shows very little wear. Those can stay. The master bedroom, replace the carpet.
It is not a poor area, but not a rich one either. I can do all the work myself, probably in a week. I have vacation to use up. In the development, places over $135k linger and eventually get sold for $115, but they are rough. I figure put in $2,000 worth of materials and my labor. Get $15-20k more for the property.
