Con Artist, Scammer
You know that 詐欺 is "fraud." An expert in fraud is someone who does this it lot, and possibly for a living. That's a swindler, a con artist, or a scammer.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own. Will help to know the reading of 詐欺 as well.
I thought you are a big spender, and you turned out to be a con artist.
I heard that there are quite a few real estate scammers out there.
"Hey, did you just call me a liar?" "No, but I called you a swindler."