My philosophy is I don't dare look at any acquisition from a make a profit standpoint. Whatever I wind up with is usually a gamble that I'm prepared to loose. My main objective is getting something working again first and count the cost later. I do this mainly for the challenge and do rely/depend on audio forum contributors for assistance but I learn in the process. Other than having things custom made, my part costs have been relatively low but the hours I spend on gear can be prodigious. So much so that I do not want to part with things I've spent so much time on. However, there usually comes a day when I must dispose of things if for no reason than to be practical as I have such limited space. This "hobby" can become a monster and take over everything. When I get to that point, I put stuff up for sale but ask whatever I think is a fair price, not what those trying to capitalize on the vintage audio craze are asking. I also stick to my guns and don't accept offers. I figure that when it's time to send stuff to a new home, it's better not to think of what I've invested.
That being said, I am looking forward to the next IA garage sale.
There has to be more to that price story ...