Signature: HB3MHw+fk12Rg0uZ5tjO+7MYQyq7tPyLQHeoCUHGZP1eEIj/69NetQOPi9yQOVNLHa48/JNshr3/voM6s0uHYI0=
Try adding the address which you signed the address from.
As for your terms, I think that it's generally fair for no ID transactions. However, 20% for 0-50 and 15% for $50-200 is worse or equal to virwox rates. I think that you should probably rethink that, potentially do 0-200 is just 15%.
Are the funds going straight to your supplier, or going through your pp then to your supplier?
Beware of chargebacks... I know that you know the drill with paypal, and I know that your country's police force is great. But if anyone's trying to buy BTC off you in the $10k-100k range for a 10% premium without ID, it's dodgy af. Otherwise they would withdraw the money and get like 1-2% over spot on major exchanges. Supplier may even blame you for chargebacks, if they do occur.
Otherwise, good luck with your venture! Nice to see another pp to BTC exchange service.