Sailing out of Avignon in Sept and need a nice hotel under $300 in a good location not far from the port.

Sailing? Really? LOL

I think they have river cruises that dock at Avignon somewhere around that famous bridge (Pont St Benezet). That would be convenient to the main center of town where the Palais des Papes is. The Mercure there is supposed to be decent.

http://www.accorhotels.com/gb/hotel-...es/index.shtml

There are two Mercures within rock throwing distance of the Palace. I stayed at the one on the right at the top of the Main Street. The other was on the left and slightly lower down the hill. Mine was modern, comfortable, and completely lacking in charm, but the breakfast was excellent and the location perfect. I would guess the other one wouldn't be much different.

I was thinking of the one at the top, basically in the center, if I understand you correctly. Mercures are decent, reliable, and usually comfortable hotels. It sounds like it's just for one night or so, anyway, it would be a safe bet and a very convenient location.

We are thinking of the same one, and I agree with your characterization entirely.