Did you look at the Carmel Mission Inn? Its not in downtown Carmel, its off Highway 1 by the Crossroads Shopping center. They did a courtesy hold for us and i don't believe they required a two night stay. http://www.carmelmissioninn.com/
My guest stayed in Monterey, on Cannary Row. For the wedding they drove to Carmel which is only 10min drive. There is more to do in Monterey especially at night. And of course they were able to stay one night. The best hotels are on Cannary Row so your guest can walk to town and not worry about driving especially if they want to drink. Hope this helps.
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