To the best of my knowledge the other side is free unless you get caught by the harbour master for dues once you've launched.
The road leading up to it can be a bit rough, and the slip appears to get covered in shingle a bit quicker than the Ferry Inn one. But unless you are a member of the ECA there are no facilities.
Remember that on the Hayling side you do have public toilets, and the pub, plus this time of year the pub car park is free, and the harbour master doesn't often bother to collect the harbour dues.
My other thought is that I'd rather leave my car and trailer on the Hayling side in the pub car park wher there are people around all day.
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