If you fancy a bit more of a challenge you could always go under haven bridge and moor up on south quay, mooring is by lines that hang down and land access is by hideous slimey ladders and it's quite a drop at the best of times.
I once had to get a dog off and back on there so he could relieve himself after eating bits of sun baked crab off the pontoon at wells followed by a fairly lumpy trip back, what he deposited was quite an improvement to yarmouth,it was an exeptionally high spring tide which made getting him off easier but dropping rapidly so had to rugby tackle him off the top of the floodwall and fall back into the boat to get him back on, not something I wish to repeat.
We got enough clearance just after midnight so shot off to berney arms for the night.
Hire boats are not allowed under haven bridge.