Quote Originally Posted by Great-Kazoo View Post
Some of the drainage issues could be due to the floor not graded correctly. You could do the drain, then have it go in to a grey water collection tank. I doubt it will be cheap fix. They'll have to cut and remove a section the concrete floor, for the pipe to be ran.
Yep, probably poor compaction before they poured the floor. Chances are it has dropped at the 'back' of the garage wall and the side walls too.
You might consider replacement or mudjacking settled areas .