The Sleep Center in M'boro is where I first went. I didn't like my sleep doctor, but I liked the staff and the facility in general. They setup a VERY generous payment plan that included the study and the machine. I paid $30/month until I could afford to pay the remaining lump sum (around $1800 total). I took that offer as that was all I could afford at the time and aside from quitting smoking, it was the best health decision I ever made. I was literally about to lose my job for dozing off at work. I had no clue I quit breathing 87 times per hour.
My new sleep doc upgraded me to a modern cpap machine a couple of years ago and the total cost of the machine was about $700. The DME company that supplied it let me pay it off in small monthly payments.
My best piece of advice is to let them fit you for a mask, but buy it on Amazon. The DME will say you need a prescription to buy a mask but it's a lie. I buy masks, hoses, filters, etc on Amazon exclusively w/out an Rx.