> Most of it second hand from eBay for half the usual retail price.

You were scammed. X520 is old enough to drive a car, the shop should pay you to get it off their hands.

Ha. I meant the rest of the equipment (USW-Aggregation, Unifi Pro Max 16, UNAS Pro, Unifi Express 7) was somewhere around half retail price.

I think I paid ~$15 for each X520-DA2 including postage.