Yarmouth has many pros and many cons: it is a useful jumping off point if heading west from the Solent, it is an attractive little town, and still retains some old world charm. Against that, it can be extremely crowded - pleasant enough if you like being sociable, but the rafting up can lead to problems if the inside man wants to leave at 4 a.m.! In recent years, it has gone 'upmarket', and is now almost as expensive as Cowes or Lymington. The advent of well heeled 'yotties' seem to have produced some rather over priced and upmarket restaurants.
Very straighforward from any direction - the pier is an excellent landmark. Coming in from the Needles, Sconce North Cardinal just inside Hurst Narrows is a useful marker. Yarmouth is also directly opposite Lymington, which is conspicuous enough. In doubt, follow the ferries!
As with Lymington, beware the ferries. There can also be a strong cross tide, particularly on the ebb, and it's a good idea to find a convenient transit and make sure you're not drifting off to one side. Other than that, motor in reasonably gently - there is not a lot of room inside the harbour, and there may well be dinghies movng back and forth. You may often be met by a harbour official who will direct you to a berth.
Other than Black Rock [see chart] and the ferries, none.
There are now 'walk ashore' pontoons, with all the mod cons of electricity and water. They are also expensive (£20 + £2.50 for electricity form a 30 foot boat (2007)).
The non walk ashore pontoons are cheaper, but this means either a dinghy or the water taxi to get ashore. (Using the water taxi rather reduces the cost difference!)
There is also the harbour wall (which is not comfortable, and usually a lee shore). You will need lee boards here (there may be some on the quayside).
There are few pile mooring left, and they would seem to be reserved for very large boats.
When things become really busy in the summer, you may have to go on the mooring bouys outside the harbour.
Showers etc ashore (you need to buy tokens for showers). Fuel on the quayside.
Chart 2035 - Western Approaches to the Solent

A view into the harbour entrance. The ferry berth is empty. Some boats are on moorings outside.

Beware! These run frequently during the summer.

A view of the town from the 'walk ashore' pontoon. The ferry berth is out of sight to the left of the photograph.
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