I have had this belief for at least 2 years and yet in my market the last 2 years had significant RE appreciation (so I was, at best, early in my prediction).My belief on the rent continuing to appreciate is based on many factors but the primary one that I use is that rents lag RE fluctuations in both directions in my market. 

No of course not, it fluctuates, some leads are great and others are... well great too, compared to the crap other people are getting.

For you as an investor, that means you can likely safely predict your cashflow and appreciation in an accurate manner without worrying if the housing market will fluctuate one way or the other.  

Costs of rehabs have gone up significantly with inflation so these things fluctuate over time. 

Keep in mind even within a market, you have sub-market fluctuations and wide variance between the asset classes (A, B, C, etc...).

I have a very basic question (almost sounds silly), I keep hearing property prices always go higher in the long term (not referring to short term fluctuations).

What worries me, is that the population in such cities seems to be decreasing, or constantly fluctuating.

However, it's worth noting that the commercial real estate market is experiencing some changes, such as the introduction of 1M new build units this year and fluctuating credit markets.

Since there is some fluctuation in rates it might be best to look for another option over the next few months/ years.

Now I understand, this isn't flipping in a matter of months, I get that, but point is, do the math, the accrual of value is steady, regardless of rates, regardless of fluctuations in the economy and world as a whole.