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.

The 200% Rule: the combined fair market value of all your identified replacement properties cannot exceed 200% of the value of your relinquished property.2.

Even if it is a combination of a few different programs. 

I estimate their combined value based on the current market to be around $900k.The goal would be to extract max cash out.

Maybe you do nothing if it is clean and functional.  

Then, you decide on the combination of these finishes that works best for your taste and budget. 

If you buy an investment first, it's got to be a screaming deal or you'll see lower returns than the combined savings+income of doing a house-hack (you got to live somewhere!).