- If every time you vote you get a receipt for that vote that can be checked if it's still valid then you can send that receipt to the buyer and he can then check that your vote is still according to his purchase - If you can only check that the receipt was registered but not if it's still valid you can't check that your vote was correctly counted because you don't know if the vote has been changed after in multiple possible ways - If you can check that the vote actually is for candidate A at any time you can sell that access to the buyer for him to confirm - If the only way to avoid all this is to also cast an actually secret vote on election day the buyer now just needs to make sure you don't go to the polling place. Posting spotters at the door is not too hard.

I don't see a way for you to actually be able to confirm your vote was counted and not having at the same time the ability to sell your vote in a verifiable way. Perfect verification isn't needed either. If you're selling your vote to the mob you'll have second thoughts about failing to deliver. If you make the process easier "honest" sellers will create the market.

> Note that frauding vote buyers this way is also possible in most election systems that have non-digital preliminaries.

Most I know are actually harder because you only get the single mail-in ballot so you can't do the double or triple voting. If you can show up on the day and invalidate your mail-in then part of same can be done. Depending on how the invalidation of the mail-in is done it can be even sketchier. But I don't consider mail-in and absentee paper votes to have enough security guarantees either way. Paper ballots, in a box, counted by adversaries is the gold standard. Everything else has a high burden of proof.