Cadillac Repair: 1993 DeVille ?codes?, e52, running order

Question
Hi, I'm trying to get my mom's 93 DeVille ready for sale but it has a few issues.  It had sat for about a month and would not start.  I replaced the battery but it still would not start without a jump-start.  Took it for a short highway drive and all seemed fine.  Used the car a few times and it started up just fine.  Three days later it starts the first time I get in but needs a jump after.  The AC has also stopped working.  I checked the codes and I got F, E52, F11, F48, .7.0, E9.5.  I would like to fix as much as I can so that I can sell the car in good running order.  Also, how does one clear the codes?

Answer
1. re-enter diagnostics and after the codes display it will stop at .7.0

2. Simultaneously push and hold the OFF and HI buttons until you see E.0.0 and then release the buttons.

3. Simultaneously push and hold the OFF and LO buttons until you see F.0.0 and then release the buttons.

4. turn ignition off for 2 minutes then turn ignition back On and re-enter diagnostics and see what codes re-appear and if they are "E" or "EE" codes or "F" or "FF" codes.