Crikey, when I think about the money I've spent on gear in the last 20 years.
What I would say is, selling something you really like to take a punt on something you have supreme GAS for, but effectively know nothing about, is just about one of the dumbest things you can do. At least for me. I nearly always end up going back. Case in point....
At the moment I've got these amps:
Laney VH100R - these are cheap as chips on the used market in the UK. I've owned many of them. I'm one my 4th one.
Marshall JVM410HJS - these are pretty rare now, and some people out there are asking Friedman levels of cash for them on the used market. I got mine last year for £850. This is my 2nd one.
Diezel VH4 - I bought this used off eBay at the start of 2018. It is my 1st one, and this amp is a lifer. It is a 2001 model and cost me £1280.
Diezel D-Moll - I always fancied a Herbert back in the day, but could never find one. Someone (I think on here?) once said the D-Moll was the Herbert's little brother, so I went and got one. I loved it. The 1st one I had was the "retro" look, which I confess I did not like very much. So I sold it and quickly bought another with the more classic Diezel look to it. So I'm on my 2nd one.
Orange Rockerverb - I'm on my 3rd one of these! These amps are killer, and are really solid workhorse amps. I've got the MKIII 100-watt version right now. It cost me £1600 when I bought it in 2016.
Mesa Boogie Dual Rectifier - I never played one of these back in the day. They were just too expensive in the UK and at the time I was a student, and had no money. So as an adult, I only just got around to getting one this year. The one I've got is a 2018 multi-watt version, and cost me £1600. Which is a fair chunk of change, but I've spent worse on amps before! And I LOVE this amp! It is amazing.
Amps I've had in the past:
Fryette Sig:X - Owned one of these 4 times. Sold it to get my Dual Recto this year. Would probably pick another one up in future.
EVH5150III Stealth EL34 - Didn't really gel with this one tbh.
EVH5150III-50watt 6L6 - Really liked the tones, but for my band the red channel was a bit too much.
Over that sort of time period.... I don't think that is too bad money-wise. Quite a bit of amp-churn there though, which I regret a bit. So now I've just decided to mostly keep every amp I get, and have a nice collection.
But genuinely, I think I've spent more money on delay pedals and modellers over the last 20 years than amps!!