I know four people who make their entire living from
vintage computing,
and they're all subscribers to this list.
There actually is "a business" of vintage computing, now that the
market has matured. Long time members of this list has seen the market
grow up from nearly nothing to what it is now...which is still small
potatoes compared to the real antiques market. This is why there
probably is no need to really worry about getting any sort of
super-certified appraisal, unless there is an Apple 1 class donation
happening.
For the record, a majority of my yearly sales are not vintage
computing related, but nearly everything is vintage technology
related.
--
Will