I'm under contract and seller is refusing to turn on the utilities. 

Usually a Land Loan is 50% of what exists- and you need a verbal nod from planning that septic, curbs, gutters, utilities, especially water, and the size of what you plan fits the neighborhood or general plan.A construction loan on land is a different thing.

Utilities, taxes (property, local vacation, & income), landscaping, furnishing / decorations / amenities, pest control, & supplies (soap, TP, etc) are the big ones on my STR calculator that you didn't mention.I'd also recommend using the enemy method to determine expected income.

Your credit card utilization is approaching the upper limits and your monthly debt payments are pretty high.

Quote from @Autumn Brooke: HOW TO SHARE UTILITIES 101You have a property with two or more units and the utility meters are shared.

You’ll be lucky to get this as a newbie.These total $188k and don’t include property & title insurance, closing costs, property taxes, utilities, staging, and all other misc. costs

That's three months of mortgage and utilities, the cost of flooring, and the cost of painting.

If tenants are paying their own heat bill, they would call the gas utility and have the unit put in their own name, but tenants can't do that if the heating unit is shared by all four units.You won't have happy tenants if you are in control of the heat and you aren't even on premises. 

Overall to me it does seem more risky, but there are plenty of success stories of people who utilized the section 8 program.

I would like to connect with you as I would like to utilize your services for my future investments in FL.