Donny,
A bit late to this game, but here's my two cents - from someone who's been working on a project for 7 years and is likely to have a few more years and never reap one dollar over what I've invested, if I ever get that much back.
I agree with many on here. Don't ever buy an old car as an investment. That's a foolish way to go as the market fluctuates and what is trendy now may not be trendy 10 years from now.
Do you want to learn how to do much of it yourself? If the answer is no, then don't buy that car or any car that isn't mostly done and driving. Anything 40+ years old will have issues. Rubber dries out, grease dries out, the plastic wiring gets brittle and cracks, metal fatigues, components don't work right - gee, I wonder if I'm talking about audio equipment or old cars? I cannot stress how frustrating chasing vacuum leaks and electrical issues can be in a 50+ year old car. And when you get one problem solved, it usually triggers another problem.
If the answer is yes, then get yourself an original shop manual and learn. The first thing I bought was a factory chassis service manual. I call it the "Bible," if that helps. I've learned so much wrenching on mine that I feel confident undertaking another project in the future, if I ever sell it. But then again, I'm also a weekend mechanic who does much of his own work on the daily drivers and I like doing this stuff.
You'll (almost always) never build a car for the price you can buy a finished (or nearly) finished one. The cost of building a car is way more than resale in 90 percent of the cases - just watch the auctions over the weekends (Meecum, etc.) Some of those cars are going from the mid-teens to the mid-twenties and they're gorgeous. Paint alone can run $10,000 for a mediocre to decent job. Bodywork is expensive. Recovering seats are expensive. An engine rebuild can run $3,000 if you're lucky. (Mine was $2,900 for a long-block).
Unless you're rebuilding a 1912 Hupmobile (and even then), parts are available for pretty much anything. However, patience will be your next lesson. If you have none, then undertaking an old car that is not a Mustang, Chevelle or Challenger is not for you. It took me over one year to find a passenger side window. Three years to find good grill inserts. Depending on what you car choose to do, you will spend hours searching the interweb, junk yards and praying to the car gods to find any parts you need.
Find common lost souls. No matter what car you choose, you'll find others out there who have the same thing. This can be very important in the restoration game - especially when parts are hard to find and/or you need guidance or just want to vent. It's been invaluable to me over the years to learn and share info and parts with others who have my car.
There's a lot more to know, but this post is already getting long. In short, buy a project because you want one, not as an investment. Heck, I don't care if you don't love the car, I didn't when I first found mine but I felt sorry for it and didn't want to see if go to the demo derby. Now, I love the beast. Learn to wrench, or at least be willing to. It will save you tons of money in the long run, even if the car is mostly done when you buy it. Don't expect a big payday at the end, even if you do find that '70 Cuda in granny's barn. Buy it as a hobby, a learning experience, whatever, but not as a retirement account.
Finally, enjoy it! Old cars are not worth the trouble and expense, and don't ever let anyone tell you they are. However, they are rewarding. I've literally brought my car back from the dead (non-running and a mess when I got it) and from the fate of the demo derby to a car I've taken to four shows this summer (though it's still a work in progress). It's totally a Dr. Frankenstein feeling. And when I consider that I've done everything (mechanically) to this car myself except for the rebuilt long block - that's pretty freakin' cool in my book.
BTW, it's a 1969 Oldsmobile Toronado.
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