Question 1053513
This isn't really an algebra question.
Setting a monthly rate on an apartment is based on many factors (age, neighborhood, other nearby rates, vacancy rates, economic conditions, etc). 
Typically you use a realtor, broker, or someone else who knows the area and can guess at a reasonable price. 
You can do it yourself using the internet as a source of information. 
You can search on price per square foot for specific cities. 
An apartment in New York City will be priced at different level than one in Boise, Idaho because there are many more potential renters.
Once you find that monthly price per square footage, multiply it by 880 to get the monthly rate.