baby!! baby baby!!

You guys I have the fever! I have been wanting a baby for quite a while now. My fiance and I are very stable. we baught our first (3 bedroom) house together back in June, we have fantastic jobs with great benifits and definitely have the means to care for a child. We always said that we didnt want kids but I have grown to love the idea. Im having one hell of a time trying to convince him. He thinks he will have to stop going to the garage and worries about stupid things like "kids make your car dirty." I think hes a bit concerned that i will not help out in the garage like I do now. I just cant get it through his head that everything will be fine and we can still have fun and work together. I need some tips on convincing him, how do you do it? I have tried everything.