Other Fuel System Tank Filling/charging problems of the 2010 Mercedes Benz GLK350

After filling up the tank the car smells and leaks gas. However, the leaks stops after few hours. I took it to an independent mercedes repair shop, they told me they need to change a unit and this is a common issue for mercedes. After spending $450, the problem came back a month later. Now, they are saying, I need to change another fuel unit which will cost me an addition $650!.

Fuel leaking/dripping after filling up with gas. The smell of gas prompted me to look under the vehicle and it was then that I saw a small pool of gas on the driveway. The leaking stopped when the tank was less than ¾ full and recurred when filling the gas tank. No damage yet, going to the dealer for their assesment.