Secondary is something that is less important than or compared to something else. Secondary can also be a result of something or someone that is primary by definition. A secondary location can refer to an alternative location. It can also be a place that is situated somewhere else in relation to the primary location.
For example, John Mulaney used a secondary location in his comedy show to describe a location from which you have no chance of returning back alive. Boats have hull identification numbers (HIN), and while the primary location for the HIN is on the rear of the transom, there should be a secondary HIN location in the interior of the vessel.
In terms of real estate, the term secondary location can refer to an area that is less advantageous. A primary area could be an area that is very desirable to live in and the reasons for that are numerous. Getaway cities in terms of traffic count, safety, accessibility, and many surrounding neighborhoods are some aspects that define a primary location in real estate.
A secondary location in real estate is the complete opposite or not as convenient as the primary one. We can define the area around the secondary location as lower-class, not so active commercially speaking. The term can be associated with a location that is nicer than average but not incredible.
Secondary locations can also be real properties located in unsafe areas or areas with high crime rates. Real estate that is hard to find or spot is also considered to be a secondary location. Properties that are surrounded by poor infrastructure or property with inadequate parking space. Secondary locations are also priced a lot lower because of this and that is another way to differentiate between primary and secondary locations.