Have same story as several others here. Put an ad on Gumtree, got text from that same number stating same name and requesting email with final price. Responded with similar message that he working on board ship, not able to take phone calls, requesting PayPal account or bank account details to pay. Will pay additional $300 to take add down then will contact courier to pick up car.
I also post an ad on gumtree then got a txt from this number, he claims he is John Gerald Klugt and wants to contact by email only because he on-board in his work prevent him to make a call. It's look like strange to me.
Put an ad up on gumtree in Australia and he asked me to email him with the final price of the car. Thanks, I see this is a scam then! Seems to come from a Californian number.