If you have sleep apnea, don't be fooled into renting a Cpap machine, from Northstar Medical or other companies. With a doctor's prescription, you can buy the machine directly from the manufacturer. Northstar Medical billed my insurance company $36,000 for $3200 of actual charges. They charged $230 monthly rental for a machine, that cost less than $600. Northstar Medical continued billing my insurance company even 4 months after I turned in my machine. I had to write to the company to report the fraud. Northstar sent me a bill for the accessories (such as mask), that automatically come with the machine.