This makes me feel more comfortable buying in Las Vegas right now...I'd be making 10% CoC return roughly with the right deal, with low probability of a significant price reduction in the future.

Or is it considered a price reduction, lowering your cost basis in the property?

Reduce labor expenses, you increase disposable incomes, reduce cost of goods, reducing cost of finished material goods, creating a compounding effect of savings that all culminate in a significant reduction in cost of housing production, increasing production capacity, increasing affordability, invigorating economic activity, raising tax revenues via the Walmart method of volume over profit margin..... 

I was able to secure a 80% LTV loan and was originally quoted 5.5% interest but asked for a interest rste reduction in return for a business banking relationship.

Even with the FED expanding its balance sheet they can't completely replace the reduction in private money supply. 

If nothing else it sounds like you could make some pretty impressive reductions in your overhead by shopping around your insurance.I pay $400 labor for pull and drops, which takes something like an hour, for one person.  

To the extent that a price reduction may make a "stale" listing appealing, worry not, you will get those notification emails on auto pilot anyways.Start doing the compare and contrast, maybe make a spreadsheet to evaluate opportunities, play a game of "spot the patterns." 

If it truly means a reduction of 20k+ we can however live without it.While on this topic, are there other features, we may not have thought of other than pool and hot tub, that have a dramatic effect on a properties earning potential?

Buy your investments based on the numbers, tax deferral/reduction is a secondary strategy to utilize. 

I don't have all the city-by-city regulations in front of me, but most will have all or some of the three "Poison Pill" regulations that slow ADU development.