I guess one of the advantages of being a long time land based visitor is I usually just send an e mail saying arriving xxx and leaving xxx+/-. Never get asked for a deposit and I always get the same confirmation #,"OK" <img src="http://www.traveltalkonline.com/forums/images/graemlins/Grin.gif" alt="" />.
You mail just want to e mail them and ask for them to call you at a specified time for cc info. BVI to US rates are cheap(comparatively).