There's a slew of other factors that can impact your rental such as the demographics, property type, size, age, etc. 

What are the sizes of the units?

If it is the first then it would seem you have a case to challenge their requirement, since as noted on the chart there isn't a requirement for a PE signature on building plans for that specific project. 

Average loan size was $248,285 and average LTV 123%.

If the garage space is 22' x 10" (typical size), this would be about $38/s.f. 

My ideal scenario would be to own a small investment company with a partner that holds a few mid-sized rental properties for baseline income, and supplements this with a few high-profit flips every year to help grow the rental portfolio and pay for lifestyle upgrades, vacations, etc.My formal education is an Electrical Design engineer, and for the past 10 years I've worked for large companies designing complex electronic (computer) circuits for things like Medical Devices, LED lighting, etc.

If there is a SFR on the property and its zoned duplex or multifamily then you will be able to build additional units if you follow the zoning code and your lot size allows.  

Hi,I'm evaluating a mid-size (40 - 70 unit) MFH property in the Greater Atlanta area.

Response rates aren't that high so you need a large sample size.2) Don't forget most people don't hear results until the 3rd-5th mailings so you need to stick to it3) Unless you're super small, you'll need software eventually or you'll ineffectively spend your time writing each letter individually, stamping, and mailing.

Although a 6-unit is smaller than the size of the CRE loans I have dealt with, some of the same credit analysis might apply.