Lawrence,
I would check the project documents to be exactly sure of what you're appraising but...it sounds like it's a footprint unit to me. I've only seen them in PA (Maybe if Ray Ohler is around he can help you out but I haven't seen him posting lately. Ray where are you???)
Basically, a footprint unit is just that, only the land under the unit is owned, technically making the project a PUD-some people just don't like the word condo so they came up with this "animal," I guess as a marketing tactic. In all other aspects, it looks like a condo because once you step out the door, everything is owned by the association.
If it is a footprint unit, you can do it on a URAR. Just list "Footprint" in the lot size box. If it is a true condo, it goes on the condo form unless it's an FHA, then you have the option of the URAR or condo form.
As an aside, you could call the association/management agent for additional info. Or, if you're in a hurry, why don't you go to the HUD appraisers webpage and see if it is listed as an approved PUD or an approved condo. That may be of some help in nailing it down. Plus you would have an FHA approval number to list in the report which makes some underwriters really happy to see, even if it is a conventional loan.
Ben