When a group of Flyertalkers no show
At the Saturday night dinner for SinDo 2010, eleven people did not show up. It turned out that all were experienced DO attendees yet not one of them called, PM'ed or emailed with regrets. As a result a table was held for 1.25 hours for them on the busiest night of the week at the busiest hour for a restaurant in Singapore.
As an organizer, some lessons were learned (fortunately there was no minimum guarantee for the dinner). Do not ask the restaurant to hold space for late arrivals. Require that payment be made in advance and non-refundable despite the much greater logistics involved in collection. Set a cut-off for payments and stick with it. Be sure to build in a considerable buffer for currency conversion costs (if at a foreign venue from one's home country), Pay-Pal and bank charges and restaurant ancillary charges particularly if a guarantee is required. Be sure that everyone pays even those who say that they are just dropping by or do not plan to eat.
This all sound rigid and tough but it has become a necessity at least at those functions that I may host and organize.