You could always try Avon Beach at Mudeford, Christchurch. Car Park backs straight on to the beach.
There is a small slip or gravel to launch on the inside of Christchurch Harbour just next to the lifeboat station at Mudeford Quay.
The car park at Hengisbury Head is about 100m from the beach.
Ther is a car park at Southborne near Bistro on the Beach. The path down is about 100m with an incline.
There is a car parking area right along the sea front, accessed from the road down to Boscombe Pier gives you access directly on to beach.
Nothing much then until you get to Poole.
A small car park at Branksome, with direct access to beach.
A small car park at the end of Shore Road, about 50m from beach.
Then the main (large) car park at Sandbanks, with direct access (50m) to beach.
Alternatively, park on the road on the inside of the harbour, and launch from there just over a low wall. Depending on tide, straight into the water or a long walk out.
In the harbour, the car park at Baiter Park is always an option.
If launching from any of the beaches, obey the speed limit inside the yellow bouys (5kts) and keep a very good eye out for persons in the water.