Just to let you know that in the end it was a bit of an anticlimax as I was out when the guy called - my husband was here and did give him some money, but that's his choice.

However.... I did use the line this afternoon on a neighbour from a couple of doors away who happened to arrive home at the same time as me. Turns out her little boy (aged 2) has chicken pox and it's causing her great inconvenience to take time off work to care for him.
I can sympathise with that, having been there myself in the past. But.....She knows I work for myself, from home, and suggested brightly that I could look after him for at least a couple of days next week so she could go back to work. She graciously said that she was sure he'd be ok to stay in my car alone for a couple of minutes while I picked my daughter up from school, as long as he was still in my view......!!!

I was pretty shocked that she could expect me to agree to that - I WORK from home, not sit on my backside and drink tea all day while I watch daytime TV, and I know enough from experience that nursing sick kids and home-working are mutually exclusive.
I did justify myself a bit, which I shouldn't have done, explaining that I had at least one meeting/appointment each day and actually felt guilty that I couldn't/wouldn't help. But I stuck to my guns - it's not like I was refusing to help out for a specific reason or in an emergency, she just wanted a handy carer for her son. (See, I'm justifying myself on here now too!)
Maybe my response should have been: "Why would I want to do that?"