I've bought a couple pins off ebay. Unfortunately this is pretty typical.

If I may recommend a tool to help adjust your leaf switches (slings & drop targets)

https://www.pinballlife.com/ultimate-leaf-adjuster-tool.html

Lots of pinsiders use Novus 2 to clean and then use Blitz wax to protect. Pinhedz also makes some good cleaners and wax as well.

Replace those balls with new asap. They are going to act like sand paper to your playfield.

Flippers may need rebuilt if tightening up thier screws doesn't reduce the slop.

Really examine the playfield closely. These ebay sellers are notorious for missing hard to reach areas or post which obviously require rubbers.

Congrats to you and your new game.