You (the purchaser of the commission) get an unlimited license to use the work you paid for, for any purpose - commercial or non-commercial - and make modifications. Dave (who is me) retains ownership of the work. Time to completion may vary. If a refund is requested, Dave will grant a refund of any money Dave received from the transaction (not including Ko-Fi's or Patreon's fees) as soon as circumstances allow. Once a refund is refunded, you give up the above rights to use any art or such work made as part of the commission.