Probably a dozen more reasons than the 5 most common/important above."

It is increasingly common for a PM to charge a "leasing fee" which covers all the costs of marketing, showing, screening, placing tenant under contract, collecting deposit and rent, setting up utilities, getting the tenant placed, etc.If the PM can't justify the cost, then they shouldn't be charging it.

Another common thing is families coming for graduations since this is a training base.

Should they be made into a small common area that the main unit also has access to?

The rent growth rate is assumed to be 2%, which is a common growth rate, and the inflation rate is 5%.

Are there common roofs?  

Some lenders might accept Airbnb/VRBO income reports or bank statements showing rental deposits, but this is less common.

Be careful with Camden and Mercer counties, these are commonly found on lists of most at-risk markets in NJ relative to price corrections. 

It's also common to encounter retail branch employees who are  not familiar with  the entities and various ownership structures real estate investors utilize since they are normally opening personal bank accounts.

Real estate investing is forgiving; the average person can still make money even with some big mistakes.Software is a common question on BiggerPockets.