How far out are you willing to go. Plymouth QAB (Queen Annes Battery) is a very good option. They offer a launch/recovery storage service for a reasonable rate. Stored in secure area with CCTV when not being used, launched with a tractor on a hard slip and left on a pontoon ready for you to board.
Dive sites are very good with lots of wrecks to get to as well as the Scilla which is very popular.
One of the only ones within Plymouth that offer a storage and launch/recover service. Unless you wanted to go for Yacht Haven Quay Drystack which is even better again!
Peter ~ Boatsandoutboards4sale ~
askboatsandoutboards4sale@sky.com ~ 07930 421007