It could be a really excellent sign if you are invited out for a really lavish meal by some potential clients in Saudi Arabia — on the other hand it might merely be a polite way of letting you down gently.
Either way it will be very difficult to tell at the time.
What is certainly true is that it is difficult to get to the point of having a strong enough connection with somebody to be able to do business with them until a certain amount of entertaining has been undertaken. View this process as a vital part of the relationship building cycle.
Traditionally, entertaining was always done in the home in Saudi but nowadays will invariably happen at a restaurant. Restaurants often have two rooms – a family room and a room reserved for men. Single women travellers are often allowed to eat in the family room. Be prepared for large feasts with massive amounts of food – but, of course, no alcohol which is taboo.
Always eat and pass food plates with your right hand as the left hand is considered unclean. (It would be quite insulting to pass food with the left hand.) Food is in fact often eaten with hands.
A service charge is very often included in restaurant bills but an extra 10% sometimes given for good service.