Vendor Problem Help

I wonder if anyone can help me find a secure One prim vendor script which is less prone to bugs when sl is having trouble.
Since I began trading I have always used a simple pay vendor script for each item I sell. It is an Asl Script I aquired free after a vending class. 95% of the time I have no trouble, customers pay the vendor and get the goods Np.
When sl has a slowdown as with most sellers, customers sometimes dont get the goods they paid for, and its a simple matter of sorting the customer out when you log on. Very occasionally though a customer has ended up with a copy of the actual vendor itself, script and all. I did not think anything of it at the time, and assisted any customer with a this problem in the same way. One incident recently (this week )however was a cause for concern, where a Customer bought an item, received a copy of the actual vendor and put the item up for sale in their own store. I realise now that my vendor system whilst simple may not be the best option. Does anyone have any recommendations of a system that has not resulted in this problem.

Well, the script can't do anything to result in the buyer getting a copy of the vendor--that's just not something under script control--so it must be that something else is going on. Either the vendor prim is set to sell copies of itself, or it's just SL-snafu (though not one of which I'm aware).

That said, there are some very dangerous vendor scripts out there--dangerous, oddly, because they *don't* ask for debit permissions. Here's why: that nifty "fast pay" option, where the buyer only gets one choice for what to pay, does *not* guarantee that the vendor script won't get some other amount of money handed to it. And if it never asked for debit permission, it can't give back the wrong amount, so probably it's not even detecting that situation. It would not be a very elaborate hack of the open source viewer to simply override that fast pay dialog and trigger the script's money event, effectively making everything in such a vendor free.

I don't know if such a hack is currently in distribution--not sure it would be a very lucrative exploit, since vendors scripted with that bug aren't likely to vend very valuable stuff--but someday somebody is gonna be hurt that way.

I obviously need to check whether I have selected all the permissions correctly, Mostly I have no trouble, but ty for the reply. If I am ever able to get near one of my vendors soon (Cannot go anywhere at the moment)I will make sure I have not made this mistake