Under current Medicare rules, you own these types of equipment after renting for 13 months. When you switch to a Medicare contract supplier instead of using a "grandfathered" supplier or other non-contract supplier, your 13-month rental period will start over. So, you won't own the equipment until after the new rental period ends. This will extend your rental period and result in additional months of coinsurance. However, the amount you pay may be lower because the amount you'll pay will be based on the new payment rates under the new program.