Re: if you live in Socal and want a Les Paul
That was about a $1,200–$1,400 guitar when new, IIRC. Prices went up a lot between that point and when I bought my 2004 Standard for $1,980 (in 2004) – though they also went to a moderately figured flame top on Standards at some point in there.
It was generally a good period for Gibson IME. I can see it retaining full original value, with the only devaluing coming from inflation, even with a little wear and tear. But I can't see a 20 year old run-of-the-mill Gibson stuff going for 50 percent more than new. It isn't like they were supremely superior guitars back then or anything.
To me, that's a steal at $1,200 and a fair price at $1,400.