It's usually about $30 for 100 minutes; lots of time. First couple of times just go for a short period; like about 7 minutes. The salon might push you to try a longer time; don't let them.
And don't cheap out on eye protection.
Pre-tanning is to be used
only to prevent the pain of a future burn. Having a tan does not provide you with
any UV protection. Wear good sunscreen.
And make sure you are aware of the UV levels where you are going. I used to think the UV index was a scale from 1-10, until I went to the Dominican and found the levels one day were going to be 12.