Much like in 3d printing, you'll find various differing opinions on what is best in the area of vinyl cutting. My personal favorite machine is the Silhouette Cameo 3 (https://www.amazon.com/Silhouette-SILHOUETTE-CAMEO-3-4T-Wireless-Cutting-Machine/dp/B01I51ME1S). It's not perfect, and is quite cheap, but it's the most versatile one I've ever used. Meaning you're not just limited to vinyl with it, it can cut cardstock to make stencils, can clearly cut shapes into regular paper or really most any material you through at it that can be cut in this manner, provided you've got the settings right. The software that comes with it is very easy to use and get used to and is compatible with many universal vector formats and can do conversions as well. Also, you'll rarely, if ever, need to repair it, but if needed, it's easy to take apart and parts are easy to find. Replacement cutting blades are fairly cheap as well.
I make decals as a side income currently but my main job is working for a custom tshirt shop that uses very similar, more heavy duty, stuff that does essentially the same thing with a different type of vinyl.
Anyway, sorry for the ramble.
I used this it comes in really handy.
I used this it comes in really handy.