You could absolutely do a lot worse that $7 or $9 an hour. A lot of technicians that start out are in a booth rental situation. You are required to pay for you own products, advertising, business cards, etc... It takes time to build a solid client base in a new place and so I feel you should be thrilled that you have a steady income. I am quite sure that as you become busier you will have more power to negotiate a higher wage, but truly, be grateful for what you have been offered. Especially if it is a nice, stable environment and the team seems happy. I also feel the same way about a 50/50 commission. This is a great opportunity for someone starting in a new place. You need to take into account all the details of your business.
Good luck. Anything worthwhile takes time, dedication, and hard work.