I'm not sure if this could cause price decreases , but it could cause appreciation rate slow down.

If they see your score drop significantly and that is unusual for you, they may decrease your credit limits or worst case close your accounts. 

The rates have decreased .375-.625% depending on the loan product and apply to rental investment property such as single family homes, condominium units, 2-4 units, and multi-family.

I guess I'm mainly looking for your experiences in cash flow, reversion values, vacancy increases or decreases as the market changes.

This could decrease your returns.

If there is a market shift towards home ownership vs renting then rental rates will decrease thereby reducing the value of Multi properties.

And then decrease again as our purchases move back to replacement cost (in say 3-5 Years)

Perhaps a decreasing rent?

I know there are a ton of these in the fileplace but mine has a unique feature I was looking for...a slider to increase/decrease purchase price so you can fine tune your ROI numbers.

I know that any time you are learning you are not wasting time, but my real question is, are there any indicators (Job growth, population increases or decreases, properties sold in the past year) that could help me with choosing an area to work in.