It is really difficult to get a good deal from a bank, unless you buy with cash, in a quick transaction, don't require an inspection and buy in bulk.

We are in the position to buy all cash but not sure if should go that route or so something like 50% cash and 50% loan.

Given you have such a low rate on your mortgage, you may be able to get some cash flow if you rent it out.

My focus is on buy and hold, cash flow properties. 

I was cashflow positive while living in the property and knew I would cash flow even more at my move out.

Is it Cash Flow, Cap Rate, COC, all three or something else?  

Most of these properties are going to take me 6-7 years to actually have positive cash flow.

We have been able to set aside some cash/savings over the past few years of marriage and are ready to invest in real estate.

Buy something in class B neighborhood or emerging class C neighborhood with higher cash upfront low leverage to ensure you have enough cashflow in worst case scenario and see how it performs.

Timeline should be Three months: Save cash.