How do I keep my dog from running away?

Question

Such as at home, I open the door so friends could leave, and all of a sudden, my dog comes rushing out of the door. I go after him, he runs even more. I stop, he will pee on some bushes etc.
If I walk close to him, he starts to dodge and run even more. I guess it's a good thing he's free from his leash or something. But there are cars in the street and I don't want him to get hurt. And no, there's no fence, this was at my relatives house, not mine.

He's a small dog, harmless. A big dog just attacked him this morning, he didn't counterattack, he's very nice. Just very adventurous and curious. I love him, his leash got lost, the retractable ones. So now I got a really long leash but I only allow him a distance from me so he knows not to stay too far away from me.
It's just he rushes out of the home. I try to go back and say bye! Hoping he would follow me, sometimes he does, and sometimes he doesn't if he doesn't live nearby.
I'm not getting a fence by the way.

Answer 1

If you are at a relatives house and you know he does this then you should leave a leash on him in the house so you can grab him whenever the door is opened, or if possible put him in a room where he can't dart out the front door. It also sounds as though he has no manners or obedience training if he won't return to you when you call him so I would enroll him in an obedience class. It might save his life.

Answer 2

get a retrever training leash.
they are about 20 feet long.
(this will take ALOT of practice)
take the dog out on the leash.
when ever the dog doesnt strech the leash to the limit reward.
when ever the dog comes back when you call, reward.
if the dog doesnt return when called, reel in the slack until the dog is next to you, then reward as if he did it by himself.
eventually the dog will understand it shouldnt be more than 20 feet from you and it should come back when you call.

Answer 3

You need to go to dog obedience classes. If you r dog runs away just sit down and ignore the dog he will come to investigate you sooner or later never hit the dog when he comes to you