You can get massive amounts of RAM and cores for a fraction of the price on sites like eBay or specialized refurbishers. Just be prepared for higher power bills and older hardware. To give you a better recommendation, let me know:
They are designed to sit under a desk or in an office corner without sounding like a jet engine.
What is your (file storage, hosting a website, or running virtual machines)? What is your approximate budget ?
Buying a tower server is a smart move for small businesses or home labs that need dedicated power without the noise or infrastructure requirements of a rack-mount system. 1. Why a Tower?
Check how many "hot-swap" bays the server has. This allows you to replace a failing hard drive while the server is still running. 3. Management and Reliability