I know you have your mind made up as to the trailer. My suggestion would be to carefully revisit that issue and be sure you are getting a four season coach that is designed for full time living. Arctic Fox and others make coaches that fit that description. For a few dollars more and another few pounds weight you might enjoy the full time life style better than in a coach that is made purely for recreational weekend use. Look at the windows, tank sizes, etc. It is more than just how much something costs or how much off the price you can get.
I purchased a new 30 foot Tango by Pacific Coachwoks that had a MSRP of slightly over $30,000 for about $21,500. That is about normal for what I would expect to get off the MSRP. Of course, the dealer can make up about any MSRP and then give you a huge discount and you still are paying more than you might have gotten it somewhere else. Dont let them play games with you on the cost of the PDI, starter kit, paperwork, etc. All is profit to the dealer, and a cost to you. Do your due diligence. Good luck!