I live in Estes Park, but haven't offered co-living up there yet. 

I knew demand was strong for RV and semi truck parking.

Find a park a distressed park, find some distressed trailers, put your husband to work. 

Quote from @Nate Marshall: Quote from @Kent Parks: Quote from @Justin Buswell: I am a member/subscriber of Pace Morby Subto, Limitless Deal Flow, and Gator.   

@Scott Schnabel actually, the cities of Hazel Park and Warren require a DL from someone at the PMC and write the tickets in their personal name.

Check out the CRREIA group which meets in Clifton Park for meetups.

In addition to those above-referenced issues related to conversions, the additional unit(s) would require a parking space and enough lot area/gross floor area to meet the requirements in 9-703. 

Parking will likely be your biggest hurdle.

There is also parking per unit and impervious cover that could be an issue.

It's thorough, easy to use and easy to modify so you can include your own special terms such as quiet hours, how trash service will be handled, parking, and anything else that is specific to your property.