Note: Scammers can scam with any kind of commission (ex: an intro commission). Keep an eye out for anyone who seems suspicious when doing business
Paying First ScamAn artist (scammer) asks the commissioner to pay the full price of a commission--or even part of it--before they make the art. They may then proceed to lock their den, block, or leave without giving the commissioner the art.
Paying After Scam
This scam occurs when the commissioner (scammer) asks the artist to give them the art before they pay anything, or pay the full amount. After the artist trades the commissioner the masterpiece, they block the artist.
How to avoid this scam
In both cases, wait for the Masterpiece to be complete. Then, you can do a fair trade--the rares being paid for the completed Masterpiece. That way, no one can get scammed.
Since you cannot trade for things like video intros, there is always a risk of getting scammed. If the person on the other end seems suspicious, insistent, or rude, they're more likely to be a scammer. It's best to do risky business with people you know, but you could still get scammed by them.