Travel contracts in Denver are coveted positions so I know you'll do well. 

Anyone have recent experience on how an ADU (accessory dwelling unit) or backhouse is valued these days relative to the main house?

This color also has accessories that might be needed like mount blocks for electric lights and receptacle boxes, so you wouldn't have to paint white ones to match. 

So, when duplexes come on the market, they're in high demand.That's why I'm a big fan of the new Accessory Dwelling Unit laws, which allow most homeowners in Raleigh/Cary/Morrisville to create a second unit from most existing detached houses (and yes, it's FHA-able).

1) Your first question specifically refers to -Attached ADU: Conversion Within Existing SFR and/or New Construction-Which reads an ADU must be 50% of existing SFR or 1,200 SF - WHICHEVER IS LESS APPLIES and it CANNOT BE smaller than 800 SF.2) So I got this text from the LA County planning site - "An Accessory Dwelling Unit, also known as a granny or in-law unit, is a living unit that may be up to 1200 sq. ft."

Does anyone have experience with building an ADU (accessory dwelling unit) on a property ?

Right now we are hoping for the appraisal to come back as single family with accessory apartment, which will clear the buyers with these current lenders, but if the appraiser sees highest and best use as a multi-family, we may be looking for backup lenders.

Looking forward to this path and connecting with you all~Accessory Dwelling Unit issue.. 

Oh and if you want an alternative strategy, depending on what state you are in, look to ADU [Accessory Dwelling Units] Great strategy to add, build, repurpose existing and new SFR's and Multifamily into smaller portions of units, Then do the furnished rentals.

If you can prove your home had the accessory dwelling unit (ADU) prior to the 2001 adoption of the new UDC, you can be "grandfathered" in.