A 76 911 targa with a busted transmission, decent interior, about 100,000mi, and it needs a new paint job (The car is yellow if that makes it any rarer). Give me an estimation of what that would cost. Its been in this guys garage that lives 2 houses down from me for at least a year, so there could be something wrong with the engine too.

Porsches are very expensive to repair, even for 70's models so it really depends on what all is wrong. Also if it has the original engine (2.7 I think) they are a bit prone to fail. Best option would be to purchase a new/used 3.0 engine, which is much more reliable and swap it instead of rebuilding what is in there now. Good 911SC's (78-83) can be had for $10K-$20K depending on condition, originality, upgrades, etc. Check out some of these links for more on 911 buying advice and values.

http://forums.pelicanparts.com/forumdisplay.php?s=&forumid=3
http://www.rennlist.com/