The Dell Inspiron 3650 sells for about $150.00 to $200.00 and with a few upgrades you have a very nice and fast desktop computer from Dell for less than $400.00.
This particular model includes 8GB of ram already installed and for some that will be just fine and you will not have to make any upgrades to the RAM but if you like to have a lot of browser tabs open or do any photo or video work you might want to upgrade the ram to 16Gb, the maximum this dell computer can accept.
This Dell comes with a generous amount of storage space at 1TB but you might want to the consider adding a second ssd drive and use that for the operating system keep the 1TB drive for storage of your files. The dell can accept both a 2.5 inch SSD and a 3.5 inch hard drive so you could have the best of both worlds. A 250 gb SSD can be had for under $100 so it’s my opinon that this is worthy upgrade.
All in all, if you total the cost of the computer, the cost of the ram and SSD upgrades you can have a very fast computer for under $500.00