Ask HN: Best way to buy second hand compute (in a future AI crash)

So, in a land before kids and mortgages I had a homelab, and want to start again.

I also think that give it a few months and the AI bud out bubble will burst and a couple of data r free worth of GPUs might come available

Buying off eBay sounds crazy so what’s the right way to find compute from sell offs, refreshed estates and so on?