What does "caravan a house" mean?

Question

I've come across the phrase in the second episode of Modern Family. Here is the context;

I'm a real-estate mogul. What?! No, I am a real-estate agent. Um, we caravanned that house. Great, uh, deck.

Answer 1

In [US] real estate a caravan refers to a showing method that some listing agents will use when selling a home. A caravan involves inviting real estate agents into a home, or more often a series of homes, listed for sale in hopes to achieve higher visibility and marketing. The sales theory behind a caravan is that other agents know what their buyers are looking for or may know of an interested buyer that might otherwise have missed the property.

The noun can be made into a verb also.

In Real Estate, what is a Caravan?

The meaning of 'caravan' here is probably derived from the historical term meaning a group of people [travelling together for protection, e.g. in a desert], and not the (outside US) meaning of 'small mobile home towed behind a motor vehicle'.