I also think that many will not want to buy it because it can contain back doors and may lead to losing a lot of customer money.
So if you are the programmer who wrote it, post in the services section as a developer and you will find more opportunities.
else:
Move this to digital goods board, so members can discussion about it.
There are no backdoors because it works purely on smart contract and the smart contract is open and everyone can view it. I am not the programmer but I have a team of good developers and this team was part of other ICOS as well . They are quite good in their work and well known developers in this dapp creation field. Needed some urgent money. So decided to sell. Selling it for 300 dollars is like giving away for free because its actual cost is a lot higher.