2 post type:
a) Building Information | Custom field: Building names, address
b) Client location | Custom field: with Building names
Building information has a comprehensive list of building information.
when I create a view for client location, how can it (search under Building information) and auto display the address?
is this relationshop? how should i do this?
It depends what specific Posts of the "Building Information" you want to display, as example if you want some "Geo Location" feature, this is not possible, as Views does not feature a GeoLocate feature.
But let's assume you want to assiciate some "Client location" to certain "Building Information", then you would as example head to Toolset > Post Typey > "Building Information" > Edit and set the Post type "Client location" to be a child of the "Building Information".
Then you can associate many of those Clients with one Building a time.
To display that then you would create a View that queries Clients, and call the parent Building Field in it, or, create a View that queries Clients and insert it to a Building Post, so to display the associated Clients.
But this is reather watery, I need to know what exactly you want to achieve, and how the data has to be displayed on your Front end to reply you more concisely.
Here is some related DOC:
https://toolset.com/documentation/user-guides/create-a-custom-post-type/
https://toolset.com/documentation/user-guides/creating-post-type-relationships/
https://toolset.com/documentation/user-guides/querying-and-displaying-child-posts/
https://toolset.com/documentation/user-guides/displaying-fields-of-parent-pages/