If it's just the chin and cheeks, you're looking at about $800 at most. I find that the cost really shouldn't be an issue. What you should be concerned about is getting a doctor that knows what they're doing. A lot of people think laser hair removal is (procedurally) simple, and it is, but knowing how to monitor irritation and use the appropriate strength at the appropriate intervals is vital to preventing nasty... accidents.
My doctor has been doing this and other cosmetic work for 15 years. I spent $1,000 total on my facial hair. His payment plan is very good. I pay $300 up front, then two installments of $200 and then two installments of $150. After that, every treatment is only $30, as many as needed. Since I'm going to need about four more, I am happy with this.
Do research. If you have a bad feeling about a place, don't go. Depending on where you live, there could be several options to choose from.
~ BB