You are making a mess of everything:
Who said you will allow peoples connect to you ?
and then once encrypted, you upload it somewhere using torrent p2p way,
Probably you're forgetting how p2p works
Then:
or even online upload services to share it over internet and broadcast it for potential buyers.
And the main interesting thing here, is that the file can't be deleted by anyone once shared ... not like online services where files deleted in a certain time or as soon as something goes wrong
Forget it, no matter how awesome looks on paper, in reality is so unpractical you are going to lose hundreds of customers. They want to pay for something and get that something fast.
There are thousands of services that offer this, starting plans at 5$ a month and you don't have to bother with hosting, availability and other bs.
PS.
In your clever explanation, you forget to mention the steps the buyer has to make for this.