Has anyone had to waterproof their basement?

[TrickyBob]

Either inside or outside? 

We are looking to do it outside, but we aren't sure what kind of cost we might be looking at or how long the process might be. 

Have any of you had to do this? What did it cost you? How long did it take? 

And most importantly, did it stop the water problems? 

[moonfrogx]

We did.

We found a large crack in the foundation that needed filling, and several spots where the steel rods they used in forming it had rusted out that needed filling. So we had that all filled, they used a waterproofing paint on the walls inside, and dug additional drainage around the outside of the house, plus put in a sump pump.

All that cost us around $2500. And it has stopped the water from coming in. In the three years we've had it done, the sump pump has only had to run a handful of times, and when it runs it's because the water is going to it and NOT flooding the basement.