I was curious if anyone has information on how radio contracts were negotiated. For example, Montgomery-Ward had Wells-Gardner build sets for them under the Airline name. Was W-G then the sole builder of radios for them during that model year? Or did they only build console models and M-W had another contract with a different manufacturer to build table radios?

The retailers could contract with as many manufacturers as they wanted to or needed to. A company the size of Sears could easily have bought radios from 10 or more suppliers in any given year because they often did local, regional, or holiday promotions. And the manufacturers did likewise and could contract with multiple distributors or retailers. Most of the bigger retailers like Sears and Wards got huge numbers of radios from one or two suppliers, and smaller numbers from other suppliers to fill out their line and cover seasonal demand.

Detrola was arguably the most prolific radio manufacturer, on their post WW2 models alone there were at least 52 different brand names and they likely built sets with over 100 different brand names during the time they were in business. They would contract with whoever wanted to buy a minimum order of radios, and put whatever brand name on them that purchaser requested.