I may be inheriting a server(s) that is about 27" in depth (2-4u) and a storage solution that's about 4u, depth not clear at this time, and I want to potentially put a ups in the rack. Maybe a managed switch as well, and potentially room to also put a modem/router in as well.

I would like it to be wheeled around if needed.

Who makes quality but budget racks that would satisfy those things?

I'm thinking 12u? I'd like to have just a little extra room. Is there a known spot where things like this are sold used?

Any help appreciated.