That way I can mobilize faster than a hotel and gobble up some bookings that would have went to my local Holiday Inn.

That is far faster and greater returns in the short term than REI will provide at this moment so is definitely something to consider. 

These four have gone much faster on the rehab side, but we really have a system down now and have great contractors who come out for us right away.  

While I could grow faster if I borrowed on that equity to reinvest, I view that equity as my margin of safety.

The fewer the bedrooms the faster we can fill vacancy too. 

The higher your income (assuming you don't take on mountains of student loan debt) the faster you will be able to build that portfolio.

You can close with an attorney and no title insurance, cheaper and faster, but more risk.For submitting offers, I suggest attorney or real estate agent (charges 3% of gross sale price).

You could certainly get there even faster, but that will depend on your ability to attract OPM.I don't think you need to pay off 100% of your debt prior to investing.

@Audrey MoorePMI is one reason but there are several others; pay off your home faster, likely get a lower interest rate, a better chance at getting a mortgage, make smaller monthly payments, you will also look like a stronger buyer to sellers.

Note I hid the boring accumulation months but you can see that the interval between purchases gets much faster at the end where you are growing your monthly cashflow $500 every 7 months.Summary:  In Milwaukee after 10 years you have 12k a month in Cashflow.