Louis (St Louis FED) maintains vast quantities of economic data, including housing data.

I have met a bunch of local investors, mentors, and friends in that group.

Assuming 50% of the income would go to expenses, until you have the actual expense data, then that leaves $600 of profit, if there is no debt/mortgage. 

I'm looking for data on construction costs to build 13 units. there's also enough room on the property with the setbacks to build (13) 8x30 garages with roll up doors on the back and front and I was considering partitioning them giving me 26 garages.

Anecdotal (and CoStar, to some degree) data indicates downtown - and East Village in particular - is overbuilt on the Class A high end for rental product. 

Do you have data from the county recorder on what improvement permits have been issued for this property, and when they were issued? 

I use this to easily have the data to give to my CPA.You can likely Google a good Excel template that you can use to customize as time goes on.I keep tenant info, AC filter sizes, trash pickup days, Magistrate info for potential evictions, Section login info in addition to the normal income and expense info. 

I want to develop a strategy to meet my RE goals, but don’t know where to go to find quality market data.

UCR data is published annually by the FBI.UCR data is reported as either violent or property crime, which then break down further into eight possible sub-crime categories.

Neither of these reports, nor the Mueller report are definitive, but when you see the same names pop up on all of these you should take notice.For more submarket-specific data plus some forecasting into the future, I like the reports from Axiometrics and REIS.