Steve,
When I used to stay on Hayling Island a guy used to advertise his boat locally for bare boat charter. Expensive though.
If you want to try before you buy why not go to the Sports Boat and RIB Show.
Heres a link to the location.
http://www.sportsboat.co.uk/news_sum...item&news_id=3
Or RIBEX.
Both shows allow you to try before you buy. AND ITS FREE. After paying any entry fee that is.