The statists are alive and well in Lousyanna. I can say that because I used to live in New Orleans.
This is simply bad law. Louisiana is banning cash transactions in excess of (1) per month for the sale of second hand merchandise. http://fleamarketzone.com/2011/10/louisiana-bans-cash-transactions-for-second-hand-merchandise/
I call this the "accidental discharge" or "knee jerk" reaction rule. Imagine if you will, the police department going to the firing range every three months. Six men qualify at once. You have one hundred and twenty men to qualify on the range. During the course of qualifying officers, there is an accidental discharge which results in some Corporal's toe getting shot off by the officer at the neighboring station. The Chief decides that to prevent further accidental discharges, only one officer will be qualified at a time. This increases overtime costs dramatically for all of the officers waiting to qualify and also for the range instructors. Overtime losses are then multiplied 4 times per year. The Chief thinking that he is brilliant and surely worth more than he makes- believes he has prevented accidental discharges up until such day that a lieutenant shoots his own toe off.
Common sense should state that any problem's cure cannot be worse than the problem itself. This is misguided statism. You cannot pass laws that cost tens of thousands of innocent people time and money while trying to a prevent a few hundred thieves from pawning stolen stuff. Not only will you end up collectively costing everybody more money in the process, but the overall effectiveness of the program will require additional man hours to monitor and enforce. And of course because it is government- nobody will ever measure the program 5 years later to determine if it was effective or not. And shit can it- if it is not. There is never a mechanism to get rid of crappy laws once they are on the books.
The juice ain't worth the squeeze.
So what does an old lawman think about this? The law will be ignored. Unscrupulous buyers will still buy when they can make a buck without getting caught and unsavory characters will continue to sell stuff. I never met a man yet, who while possessing stolen property, didn't say he got it from some other guy by the name of Joe (which he can't identify) down at the river. Or that he found it. You simply won't be able to prove anything but simple possession of stolen property- if that. Law enforcement could still recover some stolen property if that was the stated goal. There is a much better way of doing that than requiring a bunch of duplicitous and largely wasteful paperwork and outlawing cash.
In Boise, Idaho second hand dealers still do cash transactions. The buyers, generally pawn shops, simply report everything they buy to the local police on a computer spreadsheet in an email each night. They furnish a description of the property and the sellers ID. Compliance is quick, efficient, and painless. Thousands of legitimate customers and businesses are not inconvenienced for a few thieves and they are still able to use cash. I am told it works just fine.