The C+ to B class ranges is a good sweet spot.

In the lower price range, Zillow seems to get the majority of leads / inquires.

It is non-linear, meaning that small homes have a much larger $/sf factor than larger.Yes, you should see a higher price for more acreage and a garage, but there are so many other factors to consider:Style, Age, Specs - location, condition, beds, baths, basement type, foundation type, sq ft, acres, local conditions like noise sources, flood zones, school zones, proximity to airports, gun ranges - that list goes on and on.

Just adding a follow up question here: is there a recommended deductible range for investment properties?

What is the range you think each unit should cost?

It sound like you have sufficient cash?? 

There are plenty of opportunities around Denver (and the Front Range.)

Does anyone have a good referral for multifamily property manager in 30-50 unit range for the Houston/Clear Lake area?

Contractors are always slower/cheaper in the winter and if you can wait another 12-18 months, I think prices will be in a realistic range.  

The incoming rent is more than sufficient to cover any extra monthly fees incurred from the new loan product.