I had my Golden Lab sitting, staying, lying down, house trained and leash trained in the first two weeks I had him. No joke.
No matter what anyone says, they are incredibly smart dogs. Just a note of caution, keep it all up with him, they may be too smart for you sometimes. They'll try it on a bit, so be sure to keep it all up with him and he'll be a brilliant dog.
Another thing, for the first 3 months of walking him, don't let him sniff the ground when walking. Try to keep his head raised and it'll be plain sailing for the rest of his life
Enjoy the dog, the last 3 and a half years with my dog have brought me so many laughs. I love him so much!!