Hi, I'd like to insert a suggestion panel in an object layout which shows available records from another object.

I have three objects, Request, Vehicle and Garage. Garage and Vehicle has a master-detail relationship respectively. And they are both related to Request via lookup relationship. What I want to do is, show available cars in garages in Request layout. For example, if the city field in request is a certain city, I want the system to show garages and available cars in that city.