So what we’re looking at with this page is really just updating one model’s condition based on your original or ‘Record Detail’ model. So as a comparison your ‘Trade Information’ is my ‘Contact_Information’ object and ‘Related Trades’ can be my ‘Related_Contacts_Account’ or ‘Related_Contacts_Street’.
Start by clicking a ‘Related Contact’ tab and click ‘Actions’ in the upper right hand & check out the below screenshot for explanation.
I would recommend bookmarking, printing, and/or memorizing this page https://docs.skuid.com/latest/en/skuid/merge-syntax/global-merge-variables.html
It teaches you all the methods you can use to pull information from one model and plop it in another, which is exactly what you’re trying to do with this related list.
If you’re still having problems implementing this in your page, just post a reply with the page’s XML and i’ll take a look at it. 9/10 times the most frustrating issues are the easiest fixes.