Party buffet - 2 questions

[ThePartyArtist]

I am planning a birthday party at a gastro pub, for which there'll be a buffet. I have called it a 'light buffet' on the invitations, which I hope implies there'll be food but don't come expecting a huge meal!

I haven't done this before and have two questions:

1. What proportion of guests should I cater for? eg. if 40 are coming, do I tell the pub it's 40 or will there be way too much food? The pub's charging me per head. Is there a rule of thumb for catering for a proportion of expected numbers - especially if you've described the buffet as 'light'?

1. If there are left overs, what's the best thing to do with them? It'd be a pity to let the pub just throw them away so should I supply take-away boxes and paper bags, and invite guests to make themselves a doggy bag towards the end of the evening? Or if that sounds too chaotic, should I just ask the pub to box stuff up and I will hand it out to anyone who wants it (and take home the rest myself).

I'm hoping this doesn't sound really 'off' - just would rather not see food wasted, particularly when I am paying quite a lot of money for it!

I think you'll have to cater for the full number that you invite - it would be embarrassing when you ran out of plates
If you are only asking the pub / paying for a 'light supper' I doubt very much if there will be leftovers to worry about.

I'd cater for 40 and the leftovers will probably be dried out and in a state of disarray by the end and unappetising