Sounds like that salesman didn't want a sale. Maybe you should find another salesguy who's willing to open it. Then again, since I'm guessing it wasn't a TrailManor dealership, maybe that salesguy didn't know how to?!
I have a 2000 3124KB with the two opposing couches. My trailer was MCD's demo for the spring RV shows that year so it was on the lot with the option, but it was an option I was specifically looking for. I'm not sure how much earlier that was available, but definitely back to 2000 or so. The 3124 has more storage space than the 3023 -- you get about an extra foot of space in the cabinets under the bed (really one of the few places I like to have storage tho you have to be mindful that those storage spaces are behind the wheels -- don't put too much weight in them). I found the living space in the 3124 a bit more 'livable', that's why I went with it.
Vicky