I haven't tested the rules in years but I think Mt P is amenable to ADU's.  800sqft max and there is a minimum lot size, etc. 6.

As the site generates no income and has no rent roll. 

Great school system/community- 2 buildings- 6 units in each building- 2 Bed 1 Bath units-1000 sq ft per unit, appliances included, washer/dryer hookups in each unit- built in 1998 so fairly knew-Rent Roll is low and will need to be raised- Currently at 590$ per unit - Very low vacancy rate in the 15 years the owner has had them- New roofs, Air conditioners-Building structure seems very good.- Another plus is that I own 16 units just down the street so the location for me is helpful.His initial asking price was 650k and now he is thinking he needs to be at 700k.

Personally, I think you need to think longer term that just three months.As for cold calling, that's a pretty good setup to get rolling with. 

Since I'm new to this part of the RE market, I have some questions I hope you all could help with (I apologize if they are eye-rolling basic!)

Dye test toilets to check for running/leaky toilets. 

There is a very good chance a tenant (or three) will try to test your boundaries.

As April 1st has now rolled around, most property owners and asset managers will be seeing the initial results of the economy and pandemic affecting rents. 

Both units are currently occupied, with a combined rent roll of $1,500 per month.

Both units are occupied The combined rent roll is $1,500 per mo.