I have this in my apartment: https://www.amazon.co.uk/StarTech-com-Open-Frame-Server-Rack/dp/B084NXSLTG/ref=sr_1_3?crid=35U5AHSYFBFKG&keywords=4+post+server+rack&qid=1640536530&sprefix=4+post+server+rac%2Caps%2C221&sr=8-3
Has wheels, so you can roll it around when needed, adjustable depth so you can match it to the depth of your servers, and not too high (18U instead of the full 42U). If your servers don't come with rails (or as I like to call them, the slidy drawer things) I highly recommend getting some, though the ones that will work depend on the server chassis you get, so I don't have a link on hand
facebook, craigslist, etc for used.
I got mine from https://www.amazon.com/dp/B084NXSLTG
I did see it but sadly nothing, what do you think of this. https://www.amazon.ca/gp/product/B084NXSLTG/ref=ox_sc_act_title_1?smid=AV2NFXD9LK2MO&th=1