Q. I work at a desk by a window which looks out on to the street where I live. I am disturbed by the sight of the same Englishman strolling past the window innumerable times per day. I know most of my neighbours and he is not one of them. Who is he? I can’t think of a reasonable way to ask him, nor do I wish to encourage a friendship, but this mystery is beginning to obsess me.
— I.D., London W11

A. Put some marketing bumf into an envelope and address it to, for example, ‘John Brown’ with your street name and postcode, but the house number missing. Write ‘By hand’ on the envelope. Next time you see the man, rush out with a pile of post. Announce that an important-looking envelope has been misdelivered to your home and, since you know most of your other neighbours and see him so often but haven’t yet been introduced, you assume it must be for him. Sort the pile in a bumbling manner and pretend you’ve forgotten the name on the envelope. Stay silent as you sort. The delay will force him to volunteer the relevant details and once his real identity and purpose has been established, cry: ‘Here it is! Oh, John Brown. Well that’s not you, then.’

Q. An artist’s wife emails to say she hopes I can attend his forthcoming exhibition as they haven’t seen me for ages and are ‘missing’ me. I would like to reply that in that case it’s strange they didn’t ask me to their glamping party I saw on Instagram recently. I thought we were friends but only, it seems, if I can be useful by buying something. How can I expose their hypocrisy without seeming bitter?
— Name and address withheld

A. Don’t cut off your nose to spite your face. Has it occurred to you that they didn’t dare invite you to their glamping party, not because they didn’t like you, but because of the physical discomfort of the sleeping arrangements, the cheap wine and general ‘princess and the pea’ anxieties? A maximum of two hours in a Mayfair art gallery imposes none of the same discomforts. Give them a chance. Paranoia works in both directions between the rich and poor.

Q. I have been invited to the wedding of a distant relative through marriage, to her long-term partner. I did not expect to be invited, therefore would like to show my gratitude. However, there is no wedding list and they have specified on the invitation that the only gift they wish to receive is money. I find this to be slightly vulgar and frankly, given that they already own their home and are from relatively wealthy families, rather brass-necked. I do not wish to give cash in an envelope — à la Goodfellas — but would still like to get them something. What do you suggest?
—C.S., Leicestershire

A. Why not compromise with some pretty little bars of gold bullion?