But sometimes I get the grey square here on BP that shows me that something is not playing.

Such as "in 2013 the average home in addition X was X/sq ft ; due to phase 4 being sold out the average has risen to X / per square foot.

He cut out about a square foot of drywall on the ceiling to diagnose the problem.

You should shop around, you have leverage.I have not dealt with BECU, have had good luck with Red Canoe, but they don't go further north than Federal Way.  

Use zillow to get the comps you need to come up with your own estimate.To me, I have a pretty simplistic approach to estimating.In Zillow, I enter the address of my home and click submit.I then modify the default filters based on my subject property's key characteristics: Bedroom count, square footage and age of home. 

Can anyone guesstimate the repairs on a full gut single family 1,100 square foot house?

It may not list the owner, but it does list the legal square footage and where it comes from.

When running background/credit checks through the systems available to landlords, what red flags should I look for?

I would absolutely replace the cabs, with 42" uppers (replacing that inaccessible area above the doors), a 24" deep cab over the reefer with a return or narrow broom closet on the left.Here's an idea I've used for an inexpensive but attractive alternative to granite for your price level: Have a local shop fab up black plastic lam tops with square front edges, and NO 4" splash.

If I were to make a guess, I would think it would be around 150 square feet.