@Tierra-and-Nate0 As an experienced host, you already have a pretty good idea of how much effort goes into each booking, so you should at least be able to estimate how much time you will be committing to each cleaning and check-in process. You could charge a flat rate or an hourly rate, depending on how much variation you'd expect (for example, if it's a large house that could be trashed by a big group - definitely go hourly).
If you're also on-call as the guest's primary contact during the stay, this has value worth building into your rate.
A final consideration is whether you will be taking over the listing as a co-host - managing calendar, setting prices, receiving bookings, coordinating with and reviewing guests, etc. If this is all being left up to you, it would make more sense to charge a commission off of the total payout, since the listing's performance is based on your performance.