MeowBro We recommend that you first purchase a Spine Essential license, which is less expensive than a Professional license. The ESS version of the editor does not allow some advanced features such as meshes, but you can create a variety of animations by combining frame-by-frame animations.
You can upgrade from Spine Essential to Spine Professional at any time for the difference in price.

Hi! Spine ESS is 69USD at the moment, you can find it at this page:
https://esotericsoftware.com/spine-purchase

While it lacks advanced features, it can do a lot, eg:
http://esotericsoftware.com/files/Gamasutra-Carlos-Cavalcante-Tips-to-create-funny-and-juicy-character-animations-with-Spine-basics/

https://esotericsoftware.com/forum/d/6800-troll-animation/

You can start using this version, and then when you're ready pay the difference in price for the upgrade to PRO, which is a bit like paying in installments, but also good to focus on the basics first.
https://esotericsoftware.com/support#Can-I-purchase-Spine-Essential-now-and-upgrade-to-Professional-later%3F

We don't have other payment modifications, but we try to charge a price we feel is fair for all.
When considering the value of Spine in relation to the price, keep in mind that the license is not time limited. You get all future updates.