Yeah, mine was gonna be an under $5k car too. We ended up with more than 17 grand in it. Things pile up, you need parts you didn't expect you'd need, and stuff breaks. We bought our first engine out of a 1990 Mustang GT with 120k miles that appeared to be in excellent shape. 2500 miles later, the motor threw a rod. Cause? Lack of maintenance, the bearings were completely shot. If you pay dirt cheap prices, that's just what you'll get--dirt. Dirt doesn't last. If you want to drive it for a year or less, do it the cheap way, but I guarantee you will not be satisfied with the result, and I also guarantee that no matter what you will not be able to keep it under $4k. Once you get into it, you won't just want it to work, you'll want it to work WELL.

Buy a converted car and you'll save an incredible amount of time and money. I took a $12,000 hit when I sold my car, and my loss is entirely the new owner's gain.

What would I have done differently? I would have been a LOT more careful buying my parts--I would have taken precise oil pressure readings on the engine and gotten a detailed history, I would have kept my donor car around longer, etc, etc. My main lesson is that unless you do it right the first time, with the right parts no matter how much they cost, you end up doing it again, and that takes tons of time and costs more in the long run. I also wish my time and money budgets had been more realistic, but I don't think you'll find one V8 Volvo builder on here whose estimates even came close to the real numbers.