My properties are commonly rented together, and it would be great if there was some way to include 2+ properties in a single quote/booking. Currently I either have them book each separately or I alter all the charges and wording manually to note which properties the quote includes and then I manually block off the other properties included in the booking.
As you've noted, it's not possible to create a quote (or a booking) that covers more than one OwnerRez property. Because of the fundamental design of not just OwnerRez, but most of the listing channels as well, it'll likely be a long time if ever before this changes.
However, we do have a way of doing something somewhat like it, called Mutual Blocking:
With this, you create a virtual "property" that really is two or more of your other OwnerRez properties. There's still just one quote and booking for the one "property", but under the covers, all the component separate real properties get blocked off automatically.
Adding to Ken's reply above:
Once you create this virtual property, which includes both your other properties, you can then offer that new, larger guest count, listing on the channels. We tend to see even more people find & book your larger property option when they are able to search Airbnb/Vrbo/etc. by their actual guest count.
I suggested this feature because in the beginning when we only had 2 properties I had a third virtual property and it was easy to keep track of. I have 4 properties now and there’s 10 possible combinations between them that people could rent out. Their rates are all different (they all have different features and amenities) so it always takes time to quote 2, 3, or all four together for any given date. I wasn’t sure if it was something simple that could be added as like a multiple select option when creating a quote for people.