But makes expense more predictable, no major hits at one time, pay it over time.   

Can't ever predict the market, could happen next week or in the next 5 - 10 years. 

If a property will predictably bring in more money than it costs for mortgage and maintenance, you have a good start.

There are many predictions that blue collar and white collar are on the verge of a major flip and it’s just obvious by numbers.

If a property will predictably bring in more money than it costs for mortgage and maintenance, you have a good start.

They like the flexibility and predictability of renting, but purchase for investments.Understand property taxes in different markets.

- No one can predict.

A lot of investors are having a tough time with appreciation plays penciling out right now because (1) they feel that prices are elevated (2) their prediction for future appreciation is not as high or as predictable as it has been for them in the past and (3) the cash flow is low.Real estate is local though and there are opportunities at every point in the cycle (#7 above). 

I know how to track/forecast predict end of life on capital items like roofs, driveways, HVAC, appliances, etc.

Time your purchases, no one can predict either way most likely.