How we change what others think, feel, believe and do
Can't afford it
Turn whatever is being proposed into a financial consideration and then show how you are unable to afford what is being suggested.
This can be accompanied by appearing to be embarrassed, thus shaming the other person for ever having suggested such a thing.
Another alternative is to be outraged at the price.
You can also do 'can't afford it' with time.
Sorry, that would mean I'd have to travel every day and with my wife ill and looking after my mother, I just can't afford it.
How much!! Do you think I'm made of money??
I do have other financial considerations, you know. This is just poor value.
Sorry, but I can't afford the time right now.
Price objections are difficult to counter, as money is an absolute measure. If you show you are unable to afford what is being offered, it may well lead to the other person giving up and looking for someone with the money required.