Check out AirDna and pricelabs to see what the rental data says$300 is crazy high. 

I am just wondering where Bigger Pockets pulls it's market data from?

If the main goal is achieving depreciation then perhaps the weight of cap rates is less, ultimately it comes down to your goals. 

In terms of rental data, I can see rates for a lot of apartments in my area of interest, but not too many duplexes or single-family rentals.

Yes interest rates are low and so is the monthly loan payment, but the costs to keep up the house and taxes are going up, so this data point is appears lower than it should be.

Both my full time job and side gig require story telling with large data sets, I have a vast understanding of excel so would be more than happy to help with data analysis and can show you a neat shortcut or two!

Should I consider any other markets that can help me achieve what I want?

Hello fellow dreamers and achievers!!

I can look at the data until I am blue in the face, nothing beats first-hand experience. 

I would reach out to a local mortgage lender so they can give you cold, hard data on your refi.