Thank you so much for your replies - I was a bit vague too, on reflection.
I was thinking that they'd probably prefer coke and that good quality coffee would be needed (time to dust off my machine)but I hadn't considered decaf - nice tip and especially as too much caffeine literally makes me talk gibberish.
I think the idea about shortbread & Duchy originals is a great idea. I do bake my own biscuits llareggub, but historically they aren't particularly aesthetically pleasing
My plan is to go to the pub for lunch (is very nice, proper English village pub - with nice food and lovely views) I can also walk my toddler there in order to try and quell his overwhelming desire to bounce and shout.
I probably will offer drinks and biscuits - probably before they've even got their coats off
Will get some ice in the freezer and go out & get some shortbread, and those Duchy original biscuit things - I never thought I'd see the day that I'd be buying Duchy originals, but it's a small sacrifice for the business!
I am reassured that they will most likely be informal - and had I thought about it I would've realised that myself - she is a vintage interiors dealer from LA (in my head she looks like Christie Brinkley whereas I am frazzled mum who needs to comb her hair and find a top that hasn't got shiny patches on the shoulders
Thanks so much - I'll report back