There has been lots of good advice given here but I will add my two cents. I have rescued numerous buddies over the years and the one common mistake they all seem to make to to underestimate the time and money needed. I take the approach that completing a car in smaller tasks keeps your out of pocket manageable and your time spent wisely. Completing a car is like a puzzle with many pieces that are needed to see the whole picture. Complete some project like a fender or a door then drive it for a while then rinse and repeat. You need to see progress and have the satisfaction of seeing something completed before moving on. Dont try to put your arms around the whole car at once. Do all the mechanicals first. I doesn't matter what it looks like if it can't leave the barn.