How much of an obstacle?
The most difficult requirement is the franchise agreement. Maybe if Tesla split itself in to 2 companies, one for manufacturing, the other for retail and service operations, they could satisfy this requirement.
A 1000 sq ft "show room" in a mall is possible. Every Apple store I have been in has had at least 1000 sq ft of sales floor, plus back room space.
On site servicing could be possible depending on how strict the definition of "on site" is. Example, when Circuit City still had stores, the one near me had a store in the mall with an installation facility in a corner of the mall's parking lot. ("Anchor stores" like Sears often have attached auto service facilities, but I seriously doubt any mall would allow Tesla to do that.)