Yeah, you can almost stake your life on not being able to have one restored in 6 months. They only do that type of thing on TV shows!!
Using your analogy of a 30-40 year old restoration that has not been driven, the thing I have typically seen is these cars were parked and not used for a reason. Granted there will always be exceptions but generally it is because the vehicle performed unreliably or poorly where there was usually an issue with it every time it was taken out of the garage, so it just stayed in the garage. Therefore my advice is budget for the worst and hope for the best.
So depending on expectations and goals, my minimum maintenance advice to that newbie would include an engine rebuild by a reputable rebuilder. Just because an engine has new bearings from 40 years ago does not mean the job was done correctly with proper materials. Next would be tires and tubes. Next would be a complete mechanical brake rebuild bringing everything back with factory specifications. A complete steering assessment would be in order too. I would also budget for a gas tank restoration and new radiator and hope those are not needed. Then you get into lesser thought of items such as battery, generator, carburetor, distributor, hoses, lube change-outs, etc. Realistically, the parts alone on these items alone will easily surpass the initial purchase price.
And for what its worth, I can tell you that from experience that buying a running/driving car for more money does not always make it a better value. Spending a few extra thousand dollars on a vehicle that has a running engine yet needs the engine to be rebuilt (out of bearing shims, improper bearing material, etc.) does not make it a better value. Buying a 'restored' vehicle where the Seller suggests the brakes and steering probably only need to be adjusted, and maybe a quick tune-up to make it "ready to drive anywhere" generally is found to be far from factual when it is then parked in the Buyer's garage.
I do agree that "in theory" it does makes sense to buy a collector car that is already restored, ...
however most buyers will tell you that finding one that has truly been restored (-or even repaired correctly) is very difficult. Most collector vehicles available on the market are really
'Repair & Repaints' that generally leave their new owners disgusted at their purchase as they quickly learn their vehicle seemingly is a money pit. For that reason alone, I find that is the sole reason why having one restored makes sense to them.
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