Depends
My initial reaction would be to dump and swear etc.
But you have to remember this is business, whether you continue to clean it shouldnt be based on emotions, it should be based on if it makes business sense.
I went to quote a large commercial recently at the request of a new £10 4 weekly customer. Off i went, gave the quote and the cretin never got back to me with a response, even after i had asked he just ignored me. first thoughts were to dump him but..
I still clean his house windows, because its an easy 5 minutes and hes on go cardless, i think he is an ignorant mod note: language! but i never see him and i dont really care, its all about the paper.
..... and your reputation. Adam, I think you have said well.
It doesn't take long for a smart remark in response to escalate out of proportion to your reputation's detriment. If the op had clearly set his stall out to begin with when he first quoted the customer then it makes it easier to deal with these problems of customer's moving the goal posts.
"We offer a 4 weekly clean and £x, an 8 weekly clean at £xx and any long interval at £xxx. The first clean is £xxx."
Now if the goal posts are moved then the op already has the answer. The customer was clearly informed at the outset and if you skip a clean then this is the price for the next one.
If they get upset then just politely apologise for loosing them as a customer and thank them for their past business. Then move on.
We've seen it numerous times. A customer starts creating little issues with our work quality (last time you left streaks a couple of the windows, etc) which then generate into the customer terminating our services. The real reason was not us but them.
As someone says; just don't take it personally. Become Teflon coated like the Michelin man where no dirt sticks.
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