As far as buying goes. I found it very useful to have some internet found prices in hand when shopping locally. Putting the make and model you're after into Google will give you a good feel of what the prices being advertised are. Crestwood RV in New York is a place that'll pop up, they offer good prices, but they don't have any of the Minnie's your asking about online right now though.
Here's one I did find:
It's a Itasca Spirit 29B at Lewis RV in Ohio. 75% of MSRP, a good deal.
On the 27C Sightseer. I wanted a small class A. Found that going up to the 30-31 foot length that we got much more. (Larger slide, bigger tanks, couch and
dinnete.) You'd also be talking a P30 Workhorse vs. a W20, argueably a lesser chassis. We've got a 31Y Adventurer (Winnebago dropped it for 2005, our gain since we got our 2004 about a year ago), love it, came from a 28' foot C though, not a trailer (well camped in a trailer for one summer, when I was 7 I think). But we started looking at 30B Sightseer. If it had a driver's door, we'd probably own that today.