I currently own 29 amps. The only amp in this collection I have gigged is the GK 700RB/112 combo. I started the collection after I had pretty much stopped performing. At the time I owned the GK and a 6G2 Fender Princeton.
The amp that sent me into madness was Phyrexians "Grail".
SCORE!! Trace Elliot V8 coming in! ...and yes I own the actual amp mentioned in this post (it was a long drive).
I learned to play through a Blackface Fender Twin that belonged to my brother. I was the custodian of this amp for about 15 years and paid to have it serviced and updated with JBLs. Eventually I bought an MTI era Ampeg SVT that I sold around 1989. Then I worked professionally in a military band for about 25 years and they provided all of my gear for official duties. So you could probably add another 10 or so rigs that were signed out to me, but I did not technically own.
Before buying the GK I assembled a couple of rack rigs for private gigs. You can't use military gear for private gigs.
So I guess I have owned about 30-32 amps depending on how you count. If you count the rigs I have had custody over, the number is probably between 45 and 50.