As well as overall business advice because this is not a side hustle for us but something we are looking to transform into a full scale business. 

You want at least a 30% margin above costs and the NOI needs to be enough to pay the debt service after stabilization and then some.If the project looks feasible from a financial standpoint the next step is to check with the city or county planning and zoning department to get an idea if your concept will work, if you can build what you would like to build and what is required for all approvals including site plan, building permits, proffers, water/sewer tap fees, bonding requirements, inspections, setbacks, lot coverages, parking requirements, height restrictions, C/O process and time frame for all approvals.You also need to check with the utility companies and get an idea of availability and cost estimates from them for water, sewer, power, gas, cable, installation and connection requirements, tap fees, hookup charges, transformer location and relocation, power line and power pole relocation issues.

Tampa is transforming, but no where near the density or tech hub that Seattle is - case in point, my job pays 3x in Seattle then it would in Tampa. 

A typical office or retail tenant would need to install a transformer to step down that voltage which would increase their costs during a fit-out and make the space less appealing to them (or they might try to negotiate a larger TI reimbursement package from you!).  

My Grandmother has a trailer (30 yrs old) on a lot, in a subdivision, that is slowly transforming into a SFH neighborhood. 

Scares most people off, and can really transform the properties with a little bit of work.

You also need to check with the utility companies and get cost estimates from them for availability, fees, hookup charges, transformer and power line/power pole locations or relocation requirements, water, sewer,gas, cable etcYou will need ball park cost estimates from site work contractors for site work, roads, installation of utility lines etc.

With having invested tens of thousands of dollars in my businesses and living beyond our means being newly married and have little to no personal finance education, I decided to pick up a book at the end of 2018, Secrets of the Millionaire mind, which transformed my life.Fast forward a year, Ive listened/studied about 65 books on personal finance, tax/corporate law, communicating effectively, negotiation, etc., many 3-5 times.

Start with the potential gross income and work backwards from there.Check with the city or county planning and zoning department to get an idea of what you can build and what is required for all approvals including site plan and building permits, proffers, water/sewer tap fees, bonding requirements, inspections and CO process and time frame for all approvals.You also need to check with the utility companies and get an idea of availability and cost estimates from them for water, sewer, power, gas, cable, installation and connection requirements, tap fees, hookup charges, transformer location and relocation, power line and power pole relocation issues.

Start with the potential net income to determine the value and work backwards from there subtracting development costs, building costs, commissions and interest expense.If the project looks feasible from a financial standpoint the next step is to check with the city or county planning and zoning department to get an idea if your concept will work, if you can build what you would like to build and what is required for all approvals including site plan, building permits, proffers, water/sewer tap fees, bonding requirements, inspections, setbacks, lot coverages, parking requirements, height restrictions, C/O process and time frame for all approvals.You also need to check with the utility companies and get an idea of availability and cost estimates from them for water, sewer, power, gas, cable, installation and connection requirements, tap fees, hookup charges, transformer location and relocation, power line and power pole relocation issues.