[frendly]

How much money would I need to invest to make a booster myself? Like what kind of servers do I need to purchase and how do I know their power?

A lot of these guys are over-quoting on the amount of money you will need. Really what you need to find is a server that has both low monitoring on its upstream and a good amount of bandwidth to mess around with. Expect to pay like 50 dollars a month for a smaller operation of servers. There are tons of booter scripts out there but I can really only recommend UDP floods and any sort of reflection attacks. Since most of your users will be kids booting people offline, layer 7 attacks just are not that worth it to invest in. Also api access for a booter is good, as you can net in people who will re-sell access to your booter, thus increasing sales.

I would also recommend making an ip grabber that people can use for free. This will drive business to the booter, and having a "boot offline" button on the booter will make it very tempting for a user to spend the dosh to take the guy offline for an hour.