I'd like to be able to put in amortization schedule (term), rate, down payment, monthly payment adjusted to a fixed point, and get proper accruals of principal and interest by month and year.

You should expect either a balloon or rate adjustment after 5 or 10 years.What's the local cap rate for similar class properties?

40k you may find something, anything under 40k and I think you should adjust strategy.ask fellow investors in your town and spend a lot of time talking to local bankers. 

@Matthew Paul I used to be a claims adjuster and would use my estimates to negotiate with contractors.

It does not make adjustments for natural neighborhood breaks.As someone new, the key is to learn the area you want to invest in. 

A traditional adjustable-rate mortgage at prime – 0.75% has a payment of $1,210.It requires a payment of just $918, almost $300 less each month.

Is anyone using these in this type of climate?

Tile is popular in warmer climates and where there is high humidity.

Scale Adjustment Factor 1 Tear Down -60% 2 Major Repair -35% 3 Significant updates needed -15% 4 Cosmetic updates needed -5% 5 Zillow value - intentionally above average as Zillow factors in "sale ready" condition 0% 6 Major improvements 10% 7 High end value added everything 25%You'll notice that I consider "Zillow value" to be a 5 (greater than average) as my assumption is that most properties that are for sale are also above average outliers (on either side) factor out in to the "noise".Thoughts?

FYI inflation adjusted income increases is the best predictor of both value appreciation and rent appreciation.Check out http://www.city-data.com/ and an inflation calculator to see what that trend is over 15+ years, that way this doesn't happen to you again.