Roger, it sounds like you have done most of your homework. I'm not all that familiar with either coach, but I do have a couple of points that you will need to consider if you haven't already done so.

The first point concerns weights. On your test drive, swing by a CAT scale and get the actual axle weights of the coach. You can guess at how much fuel you will add to get the tank full, and add that weight to the axle closest to the tank. Figure 6 pounds per gallon for gasoline. Water is a variable. If you have plenty of CCC you can travel with a full tank of fresh water if you want. If you are low on CCC you can travel with a quarter tank of fresh, just enough to flush and make a cup of coffee.

Second point is also about weight. What is the GCWR, and what is the difference between GCWR and GWR? That's the most your towed can weigh. Again, you can move things around a bit. If you can tow more than your towed weighs, you can move some of your stuff to the towed when traveling and move it back to the coach when parked.

Since you already have a MH you have a better idea of what you want/need in this coach. Just remember that no coach is perfect. You know to check the date codes on the tires and batteries, etc.

As for private sale or trading in your present coach, that's up to you. If you have the money to buy the new coach outright, you will probably be money ahead to sell the old coach yourself. Remember that the dealer has to spend money on any trade-in just to get it ready to sell, and then they need to make a profit on it, no matter how long it sits on their lot. On the other hand, the less they have to spend to get it ready, and the faster it sells, the more they can offer you. When you take your old coach in to be appraised, have it ready to go on the lot then. Do as much of the detailing as you can. Don't worry about steam-cleaning the engine, though. Everything else that you can do, do. Get some of that tire shine stuff from Walmart, wash and wax the coach, clean and polish everything inside, etc. Look at the coach through a buyer's eyes. Have all of your maintenance records in a binder, and all of the manuals together.