not shure which license do you have in mind ? ... renting ?! ... interesting !
guess you're burning more money to setup the rental-contract and keep your related paperwork tidy, than the license would cost you.
but sometimes business-ways are mysterious ways ... ?! so ... do it the scottish way: reset the config of the VM to default after the "lease-time", make a backup and rent it to the next customer
... if there's no next customer, put it on an usb-stick and as an ace in the hole, reuse it as a christmas gift for your nephew ?!
( you see ... the oportunities for savings with a MTik-CHR-license are shoreless ! )