After waiting several years, I recently purchased a used longarm machine. I made my purchase outright so that I would not have any payments on the machine and feel pressured to take in work immediately, which is why it took so long to be able to get it.
One thing that I am giving myself is TIME. I work full time outside the home, so evenings and weekends are my 'play time' on the machine. I would dearly love to have my own longarm business and am going to work toward having one. However, I won't take in someone else's quilt top to work on until I feel confident that I can do a great job on it.
The machine I purchased is a Nolting, and their customer service and support is unbelievable. They go above and beyond to help their customers. This is something you need to consider. Make sure you factor that into your decision. You need to be comfortable with calling someone for help and being able to get that help.
Good Luck!