What you want to do is combine pieces of both of your options together. 

She decided to combine two rooms to make a gorgeous master and a "pocket office", versus keeping the 4th bedroom.  

For example, they can finance up to 70% of the ARV meaning, if you have a perfect 70% deal (purchase price and rehab are withing 70%) they will cover those cost for you.you will still incur closing cost, taxes, and insurance cost though for example.True 100% financing (ZERO out of pocket) typically requires solid relationships with private lenders or a combination of hard money lender and private lenders.

@Julia Jordan Does REI Grow have this function now?

My personal residence payments are less than 15% from combined personal income.

Usually buy, hold, cash out refi and buy more with cash out funds combined with my own funds and this has been a good equation for me heading to #12 closing Monday. 

Can your combined income support two mortgage payments in the event you don't get a renter quickly? 

To combine the two into a land purchase and construction loan you need to demonstrate on paper exactly what you plan to build and that the planning desk allows this without a conditional use permit/hearings/delays/neighbor complaints tying you up to wait 24 months to start.

It will decrease your cash flow as your single payment will be higher than the multiple payments combined. 

Most cleaners are not going to comply with your PMS platform protocol for cleaning and 98% of the functionality that you are going to use a PMS for will be messaging.