Setting the Space appears to be good - but very expensive.  

If it is a restaurant, is each space individually metered?

These houses sold for $100k+ in the past so there is space for both cash flow and appreciation.Inventory is getting tight in my target burbs so I'd say move now and see how it goes, it's a small bet at these prices.

why not offer to bring him in as a renter( seperate business between you and him) and that business pays you ( the owner of the property) rent for using the space ?

There is also a large walk up attic space and eventually plan to add dormers and finish it.There are two electrical boxes currently, one for each floor.

It works well with my apt buildings and retail spaces, but not residential.When you back-door transfer your little house after the fact, don't forget to address your title insurance and property insurance.  

If you don't mind would you share the cost of the park, how many spaces, how many park owned homes are there, what are the expenses, how did you finance it, is it city water/sewer, and what tips do you have?

After closely reviewing the current office space market in the area, seems like the average asking rent is anywhere from $18sf/yr-$22sf/yr  current tenant is paying close to $16sf/yr.

If they are comfortable with being in the stock market and 401ks give them the best options that you can in that space.

As a resident, it is exciting to see a mixed use space come to fruition and I can certainly see that there is lots of potential.