As a CPA and QuickBooks Pro Advisor, I would request that this integration utilize items, invoices and bills and not journal entries for entering data. It allows much more flexibility for accountants. I think flexibility is important as property managers will have varying situations. Think about utilizing locations, classes and sub classes for recording property owners, properties or booking channels. Customers and sub customers for recording booking channels, owners or renters. Additionally, some will want to use a single customer for all bookings to keep the data free of unnecessary customer data. You also have "Jobs" which are just sub customers that could be used to isolate individual stays while minimizing renter data. That is pretty off the cuff but I hope it helps.