This decreases the AU's credit utilization and shows an aged card.  

I have also heard (not sure if true) that some bank compound interests twice a month and that making two payments a month would significantly decrease the overall amount of interest paid over the life of the mortgage.

The local market in the Bay Area will not fall from increased supply but can from decreased demand.

That decreases the ROI and Cash on Cash return.  

Your income will decrease before it increases.

This is a small one entry/exit 25 home neighborhood.Two things concern me:1.The neighboring property decreasing my possible sell price.2.

The population continues to decrease. home buying doesn't necessarilly correspond to population.

You can decrease expenses by looking for efficiencies (ex. more efficient fixtures and materials to save on water and electricity). 

I don't want to get in right before prices or values decrease.

Increasing your down payment by $10k will decrease your monthly P&I by about $50.