I bought a 30 year old house last year and am ready to tackle redecorating the finished basement. It has a drop ceiling with very dingy (but not stained) white 2 by 4' ceiling panels. The panels seem to be structually sound (not sagging). They are just dingy. There are three rooms with a total of 60 panels. If I want to paint them, how do I need to proceed? Do I take them down? Do I have to wash them to get paint to adhere? What kind of paint? Do I need to start with a primer? I am on a limited budget, but would I be better off to replace the panels? Any advice will be greatly appreciated!

We live in a 1800sq ft ranch here in ND. I have put 2 bedrooms in the basement, plus adding a family room and bathroom (in the basement, but not yet). We have forced air elec/gas heating with central a/c. There are 3 cold air returns upstairs. The basement is always about 6-8degrees cooler than upstairs. Should I put in a cold air return in the basement?? If so, where in relation to the furnace? I can get to all the heating/return ducts so that is not a problem. I thought perhaps if I were to put 1 or 2 returns in the basement, then I could just have the fan blowing air in the summer and only turn the a/c on on really hot days (what few of them we have here). Any info./help would be greatly appreciated. Thank you - Dave