Has anyone figured out how to make this work?

Prewiring surround and maybe a 4 zone audio system for super cheap or free in specs, counting on a high percentage of calls from owners once they purchase the unit.

I have many builders who I could approach with this. Most that I have talked to already aren't interested in spec'ing a prewire.
I have thought it over with lots of different options and prices for different projects such as, condos, homes from $250 K and up and I was just wondering if this was working for any other business.
Thanks,
Jason Walter