I posted an advertisement on Gumtree about selling my cat scratcher barrel (used). Somebody named "carly boggy" sms me first then asked me get back to him with email. I thought it was a real customer. He told me that he was from United State of America and he wanted to get my cat scratcher barrel for his child who is living in Thailand. My item costs $30 but the shipping it to Thailand by airmail will cost additional $30. He said he doesn't mind it and asked me to give him my payment details. I was suspicious and found out that it was a scam. But I gave him my email address for "paypal" account but I didn't connect my paypay to my credit card an there is totally $0 in my paypal. I didn't lose anything but please beware of those kinds of scams if you are selling online. If you are living in Singapore, it's better to deliver directly to the customers and receive cash. I think it will be safer.
Source: Scam Alert Singapore