I used to work for a manufacturing company that started out as a married couple making Christmas ornaments with a $2000 laser cutter/engraver. Screen printing

I used to work for a manufacturing company that started out as a married couple making Christmas ornaments with a $2000 laser cutter/engraver. Screen printing is a pretty easy business to do out of a garage - you can either print and sell your own designs or print for others. Unless there are already a lot of screen printers in your area odds are there are businesses and organizations that would love to make some cheap swag with their logos. I haven't checked but I have to imagine there's a "xometry for screen printing" service out there that you could probably get semi-consistent work from. Honestly though, so long as you don't need to quit your day job today, you can probably find some good deals on some used cnc equipment that will let you make anything while staying in your current price range. The difficulty is not in determining what's possible but rather what's profitable. Most garage manufacturing companies tend to make some incredibly niche thing like a bracket that allows you to stick a camera on a particular item used for a particular hobby; stuff that anyone could make but no big companies care enough to develop. Most of the time these are tinkerers who make lots of little widgets to solve their own problems and one of them eventually takes off. If your goal is just to make money, I would suggest selling products that can be made by some service like xometry until you stumble across something that's popular, then you can bring manufacturing in house to increase your margins.