Bit of a dilemma. I run a (small) business, 3 of us in total. I've organised a xmas lunch with myself and my employees and put up on fb asking if the place that we're going to is any good. A close friend of mine responded and asked if she could come along too (smiley face, wink face) I said yes of course, it would be lovely to have her! Then I realised she might be expecting me to pay for her too, as I'm paying for my staff. I can't afford to pay for another but I don't know how to say : you're welcome to come along but you're paying for yourself. How do I put this tactfully? Can I?