Why not tell the dealer you honestly are wrestling with the decision and say you are inclined to wait. Maybe he'll do a little better?
If he can't, I vote in the Buy Now column and say plan some great fall trips, weekends if you still work, getting to know your new treasure and working out kinks. Autumn is a great time of year for RVing. Then you'll be ready to hit the road without delay next season.
We just got back from a memorial service for a friend who retired with plenty of money, was doing some travel and then nine years ago at 63 got one of those diagnoses you never hope to hear. Life changed for them in the blink of an eye. He never got to see Mt. Rushmore, and had grand kids he would have loved to take on family trips. He said he was living vicariously through us, and always signed his messages, Life is Good.
Life is also short. Go for it.