The geocoder used by the Google Map API is not the same one used by maps.google.com and can sometimes show different points.
The most exact way to show a point on the map is to use coordinates.
You can find coordinates for address by going to maps.google.com and searching for your address. Then add the following in the address bar:
this will bring up a javasscript alert containing the latitude and longitude for the address, you can use these in pro Maps