> nowadays I say no

I sympathise with you. I do feel that consultancy and freelance had always had this issue where bad practices in client systems introduced by careless people ended in your shores when clients phone you asking for help. This used to happen with poorly maintained codebases or broken implemented projects done by competitors. Most potential customers are likely to be past or future victims of careless rivals of yours. Is it sustainable for you to ignore past customers that were victims of careless rivals?

I am not judging here just curious about your thoughts on this.