You'd want to see all the known area's and prod them with a screwdriver MOT testers tool. Rear door is rotting in the usual place, I suspect the front legs and sills aren't much better. Got to say, a late 3.2 Elite or MV6 is much more preferable than that one to me and pretty much all of those are starting to rot in all those places now.
I think you're being very optimistic there, as most are much more likely to be one robust inspection away from being condemned. The MOT tester's tool is gentler than a screwdriver...
I was being polite so as not to offend the remaining Omega Owners on an Omega Owners Forum!
One of mine has had rear arches, sills and chassis legs worked on (Pictures in Gallery) so all to aware of the rot spots
Still enjoy driving the car though, even though they completely outclassed in every way by pretty much anything more modern in the same market segment that the Omega was in.