HI. First off a little context.
I'm getting a lot of interest in my services (Great!) However the reason I gave up freelancing was because people would claim to be interested in hiring me (and have sufficient funds) lead m down a rabbit warren of extensive q&a, only to find out that they didn't have the money. Now bitcoin with the ability to sign and verify message should allow an easy way to verify people have control of a wallet with enough funds. However people seem reluctant and non forthcoming.
I see two possibilities
1) They are lying and don't have the funds. 2) I'm asking in the wrong manner and they think I'm trying to impersonate them rather than verify they do own the account. So how do you or would you ask? Is there any kind of common term used in the crypto community? Please stake your signature? Send a verifiable message to me? Prove ownership?
Even if they verify control of sufficient funds, you still have to rely on them actually paying.
Wouldn't an escrow solve your issues? If you don't know the exact cost of your work, then have them escrow a minimum, at the very least, or perhaps even more than eventually required. Escrow could simply return any funds that are in excess.
This way, you know they have at least the amount in escrow, and will have a neutral third party to rely on making the payment.
There are plenty of trusted escrows, even some who don't take a fee.