. $1,400 for a 3bed/2bath gets bumped to $1,750, then I add in the cost of utilities, TV, internet, and landscaping. 

Utilized our LOC to purchase.

The calculation for calculating NOI for a NNN leased property is a follows:Rental Income+ Reimbursement Income (Tenant reimbursing the landlord for operating expenses)= Subtotal- Vacancy/Collection Loss (% Applied to the subtotal)= Effective Gross Income- Real estate taxes (Typically reimbursed in a NNN lease)- Insurance (Typically reimbursed in a NNN lease)- Maintenance (This will depend on if single-tenant building or multi)- Utilities (Could be nothing is single-tenant building)- Management Fees (Typically reimbursed in a NNN lease)- General/Admin Expenses (Typically reimbursed in a NNN lease)- Reserve for replacement (Tenants do not typically reimburse for this)= NOINOI/Cap Rate = Market Value

I have an investment now where my net cash flow is more than my Mortgage (PITI), water, and utilities combined.

If not you need to account for them.In your expenses you're missing: Vacancy (8%), Repairs (7.5%), CapEx (7.5%), Management (10%), and snow removal.The listing doesn't mention if the utilities are split out?

Of course there will still be other expenses (taxes, insurance, repairs, utilities), but this is a viable strategy.

The utilities are a ballpark estimate from online data. 

Will they lend to a park that has majority park owned homes and private utilities?

I've also used the assessor website to find all out of state owners assuming they are rentals for specific neighborhoods I target for either property management or if they want to sell to me.Depending on your area and which MLS system is utilized, Realtors can potentially get other specific lists.

You shouldn't have any utility costs on SFH.