@BaiLee Ashworth, as a C182 owner here could be a possible case:
$50K: All cylinders need to be replaced + bottom end has corrosion, etc
$2K: Some prop governor work
$1K: Magneto's need work or
$2K: Several hoses will need replacement
$3K: Fuel bladders will most likely need replacement.
$1K: New tires, tubes all around
$1K: Brake work, new battery, new ELT
$2K: Some exhaust work (maybe even more)
$5K: Getting basic NAV/COM working again
$6K: Various AD's over the past years not covered in re-work above
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$73K - Just a guess but at least gives you a closer to worse case number to think about. And all of this won't be done in a week. If you or your friend is a A&P , IA you could really lower these numbers a lot, perhaps to less than half. But if you have to send it all out, think 3+ months (minimum).
Another thing about this type of find is if you use a A&P (someone not biased) to come and look at it (which is a good idea) it might cost you $1500 or more just for the estimate and the bad news.
If the engine (bottom end) was miraculously good, I would still think $15K or more in top end work to get decent Continental compressions again, no valve issues, etc.
I also wonder about the prop. These old 2-bladed metal McCauley props seem to last a long time.