You'll also need to get a 2nd to 3rd generation car aerial adaptor dual fakra splitter connector converter cable (PN V7L6051551).
You can use your current sat nav antenna.
You might need to replace your CAN gateway if your Golf isn't from late 2007 or from 2008.
The last thing you'll need to to do is VCDS coding to get the RNS-510 to work properly.
You can get the 2015 maps online for free as well.