The best deal is the one you take, based on your budget and feel about the unit you're looking at. I'm not sure if that answers your question. Talk to some RV dealers, tell them what you're looking for, and see if they have anything close, maybe as a trade in, then start the process. I would think buying private might get a better number, though.
2018 (2017 Sprinter Cab Chassis) Navion24V + 2016 JKU (sold @ ????)
2016 Sunstar 26HE, V10, 3V, 6 Speed (sold @ 4600 miles)
2002 Roadtrek C190P (sold @ 315,000kms)