BGS - We have told our friends to budget $120 per day and $200 for the day we're on Anegada (plus an extra few hundred overall just in case...). They have, prudently, already changed this amount from £ to $ given that our brain-dead country will be walking its economy off a cliff in a few weeks time.

This figure includes half the mooring fee.

We generally tend to do most drinking aboard (given that a bottle of rum costs about the same as the average painkiller ashore!)...but always a few drinks ashore and our White Bay and Cow Wreck days will be far more. Generally planning for a light lunch ashore and then aiming for takeaway to eat aboard most nights. Again, first night and Anegada will likely be proper eat ashore nights.

...oh and have told them to be prepared for the airport taxes each way on top.

No idea if this number will be correct. As everyone says, you always end up needing twice the cash and half the clothes!

Given the amount the boat and flights cost, its probably better to manage people's expectations and have them budget more than you think they will need. Better that they are pleasantly surprised, rather than feeling the pinch whilst out there.