Wondering if some investors in my situation evolve to full PM by buying a service contract ($250-500 /yr) to handle break-fix since the workload to place tenants is usually once a year and more predictable.

@Mike Cumbie  You  cannot predict tenant behaviour in the way you are claiming.In 2014 we filed eviction against 2 tenants.

I have my B.S. in Applied Mathematics and Statistics and currently pursuing a masters in Predictive Analytics.

I believe 2018'will be slower and end around 4-5-% and after 2018, depending on what happens with the overall economy because many predict a "Depression Coming" in 2018, the RE market could see flattening or a loss in appreciation due to an overall economic slow down.

Interest rates below 4%, for most of 2017, and predicted to rise, as Feds plan more increases.3.

(It was me who guesstimated it down to a "95% Refi" assumption).However, have you done a "poor job" with your "$200/m cash flow per door" prediction?

The maintenance can be another variable that can be tough to predict. 

Without having a validly executed incorporation of your business and placing those properties into a business, there are very few ways to protect your assets with any degree of predictability.

The numbers may make sense but usually they are in high turn over areas, high maintenance areas, not so great neighbors and the predictions turn out much lower because of the costs involved to maintain them.The three best cash flow areas I know and watch is areas in Tennessee,Indiana and Ohio.

The hardest thing to do when analyzing a vacation rental is predicting the income.