I know it's really difficult but if you contact different suppliers for samples and try them out for yourself you'll find one you like.
Basically you want a solution that is a reasonable price for you to buy, has a good colour/ range of percentages, has a good wear off and then other things like smell, retail products , etc.
With regards to the machine you want one that will meet your demands, if you will be doing a lot of tans back to back then the TS50 will be the one for you, but there's lots of threads on machines for you to check out.
You can train with any company, buy any machine and use any brand of solution. Train with a reputable company and shop around for the best deal.
You can get samples from most companies once you've done your training xx