I looked to see if a windlass was an option on a 280SD (Sundeck) in 2007. There wasn't a 280SD in '07. I looked at the 280DA (Sundancer) for '07 found one. Assuming you meant a DA, then there were 2 windlass options for that year: an chain option and a rope/chain option. Both appear to use a Lofrans Marlin Lo-Profile vertical windlass.
This means that the factory has done the engineering necessary for a windlass to work on the '07 280DA. There is no reason, other than labor cost, that you cannot add a windlass to your boat and for the installation to look and work just like a factory installed windlass. The windlass usually has a master solenoid in the bilge, wiring to power it, wiring to/from the instrument panel, wiring to the bow (multiple conductors for both power and windlass control), switching relays at the bow, and foot switches at the bow. Most of the labor cost will be for removing parts of the interior of the boat to get access so the new wiring can be pulled forward tothe bow from the bulkhead/helm area. Your boat may already have some of that wiring in place if it was part of the standard wiring harness. Additional costs will be the bow pulpit/anchor roller, anchor, anchor rode and the windlass itself.
Our dealer in Florida adds windlasses all the time when new boats are ordered without them. It could be that you just asked the wrong guy at the dealership. The service manager or one of his service writers might get you closer to the answer you need.
