That’s not true.
At least it’s not true almost all the time. Very few of your prospects literally can’t afford it. What they are really trying to say is, "it’s not worth it." As in, it’s not worth reprioritizing my life, not worth the risk, not worth what I’ll have to give up to get this, not worth being in debt for.
One response to repeated cries of "I can’t afford it" is to lower your prices. A better response is to tell a better, more accurate story, and to tell it to the right people. The best response is to make something worth paying for.