I was in the County office yesterday, and noted a chart predicting a 15,000 unit shortfall in homes in 2030. 

maybe the phone directory could help if one could predict which city they live in

One can not predict what the bank will do.

Obviously no one can predict rates in 5 years so assume that will be what it is, but is it still typically another 5 years until the next balloon payment or refinance and a 20 year amortization? 

No one can predict the future.

Timing when to sell is hard to predict but now would be a win for you either way.

Conventional wisdom states that holding stocks long enough (e.g. 20+ years) should give you a nice, somewhat predictable average rate of return, based on long term observations of market appreciation. 

It is impossible to predict.

I would like to help her out but rental market value is only $1300 and there is no equity but there is a potential/predicted increase in value of 8%.

I think you will find your next investment property pursuit will have a much more favorable interest rate and you will be more aware of the financing in general and be able to predict your bottom line after closing the finance with a bit more accuracy!