Usually the lender will arrange for the appraisal and charge you for it. Normally, you won’t get to choose. Lenders are not required to cancel PMI until the loan balance falls below 78% of the original purchase price. You can request cancellation when it falls below 80%. (You may still have to pay for an appraisal because lenders are not required to cancel if current value is less than what you paid.)
You can also go the route you’re going, but most lenders, as allowed under federal law, can also require that the loan be at least 2 years old, with a good payment record of no lates in the last year. If your lender has that stipulation, you’re out of luck for the moment.