But the main thing to keep tabs on is interest rates, jobs growth, demographics and buyer  sentiments.

As Greg said, they're a function of interest rates but they're also a function of investor sentiment.

>If cash flow is the objective I would probably not recommend San Diego.I see this sentiment expressed a lot but historically it is not accurate.I suspect the cash flow on my San Diego rentals exceeds the cash flow of >90% of the nation and that most of the RE that does exceed my cash flow are areas that typically are not associated with having great cash flow (places like San Francisco, NY city, Santa Barbara, LA, Orange County, Honolulu, etc.). 

It is sentimental because it's the only thing I have to show that he may have loved me (probably not though).

The observation in this case is that barring extraordinary circumstances, the flow variable can (and does) change much more rapidly than the stock variable.The systemic contributors (ie: policy, lending environment, consumer sentiment) has an outsize effect on the ability for new units' pricing to move much more rapidly than existing units (ie: rental units), both up and down. 

It's more of a measure of how desirable a property is to the investors (i.e. investor sentiment).

@Michael Ablan Well I appreciate the sentiment but so far, I haven't found one that will waive these.

**This doesn't mean rent-to-price ratios are useless though**, which was the OP's sentiment. 

I echo @Travis Biziorek and @Dylan Tanaka 's sentiments.

@Joshua Thibeaux, I agree with the sentiment of others on this thread that these courses can be long on marketing and short on value.