Over the last year I can’t remember more than 2-3 customers who have not had an outside tap,( a bigger problem is terraced houses that have the tap at the back and no access)
You have 2 options, get a hose connector that fits the kitchen sink taps or ask a neighbour if you can use theirs, I tell them my machine uses 80p an hour to run, I’ll give them £10 if they let me most just tell me to go ahead especially if they are good friends with the customer