I look at every single item in the pro forma and imagine that it is complete BS, and see if I can challenge it.

It would cash flow nicely.One item to plan for from the beginning is the exit. 

Without knowing any of your financial position of your work or side hustles it is hard to give you exact advice because you may be able to carry these homes until they are paid off and in that case they would provide solid returns, but there are likely better real estate investments out there.  

In my area (near the beach) its mostly families and they want cabanas, baby items, chairs, coolers etc that we do not provide but I have a local vendor that delivers and picks up these items and charges a few dollars per day for each item, and give me a 20% referral. 

A savings to put deposits and another account for everything elseyou don't need separate bank accounts as accounting software will classify all of those items.

Basically almost all the items you mentioned when traveling can be written off to a certain extent.

You make the payments to the lender.Oh, and just in case, there are more items to know about when considering a "sub to" transaction but this is just a comment on the payment aspect. 

Look at insurance and tax costs, those two items are the biggest killer of cash flow.

@Jennifer Fernéz I run sum numbers for you with our tool, see comments and pics below before refinancing and post refinancing .Financial Breakdown: Purchase Price: $200,000 Mortgage (LTV 80%): $160,000 Interest Rate: 6% (30-Year Amortization) Mortgage Monthly Payment: $959Upfront Costs: Down Payment (20%): $40,000 Closing Costs (3.5%): $7,000 Renovation Costs: $15,000 1 Month of Carrying Costs During Renovation: $1,548Total Upfront Required: $63,548Year One Rent: Monthly Rent Income: $2,000 1 Month Rent Losses during renovations (-$2,000): -$167/month distributed over 12 months Total Rent Income: $22,000 per year => $ 1,833 per monthMonthly Expenses: Mortgage Payment: $959 Property Tax (Assuming $3,000/year): $250 per month Property Insurance (Assumption): $100 per month Utilities (Hydro, Gas, Water): $275 per month Assuming 5% Vacancy: $92 Assuming 0 % Repairs & Maintenance first year because unit has been recently renovated Total Monthly Expenses: $1,676Monthly Net Cash Flow: $157Post-Renovation Refinancing Strategy after 12 months:So far, we’ve purchased the property, completed renovations, and rented it out.Next, you can approach the bank for a refinance to consolidate a portion of your initial investment into a mortgage.

This is just one item.