I had a good run in Los Angeles during the late 90s, right after I arrived there. I would go out and find 100w Marshalls from 67 and 68 from 800 to 1200. I would buy as many I could, pick the best ones and sell the other ones. I've got to a point of having 20 of them at once, in a single bedroom apartment in Hollywood! not to mention the eight basketweave 4x12 cabs!!! lol
But when it came time to invest into my studio, I sold most of them and kept my best sounding 4x12, slant with 20w GB, and the two favorite amps, a 66 JTM-45/100 and a 65 block logo JTM-45. I still have those.
Same with original Fuzz Face pedals... had 18 of them at once, and all original and amazing sounding ones. Kept only the best sounding germanium(an NKT-275) and the best sounding silicon(a BC-108c). Still have those too.
But if I knew the studio would not be profitable, and I would end up closing it anyway, I would've kept all the vintage amp, guitar and pedals I used to have.