Everyone already knows someone who can sell them a house in the US.With over 15 years of experience combined in international travel and Airbnb hosting, I am now a full-time consultant that helps Americans purchase property and set up their businesses abroad.Me and my partner own three apartments in Croatia that I manage myself remotely.

My question is what have people used with success to best track their time/investments over the year?

I have it if you want to message me your email I can send it over :)

The property has been vacant for over a year and is in terrible shape.

I plan to buy and sell 10 or so more over the next few years.

I agree with @Peter H Derry, the neck area will boom over the next 5-10 years.

We have over 20 yrs of experience in managing here in Memphis. 

What are your concerns?

That said, the appreciation has been very high over the years. 

Quote from @Sherief Elbassuoni: Whenever I have cash, I put it as a downpayment for a new rental.Even if you got 4-5%, this is less than inflation, so your money is loosing valueMonth over month inflation is more current information than year over year...and it has been near zero in total for the past nine months and negative for 5 of those 9 months.