My home is 30 years old. Recently I pulled the paneling off the basement wall to prepare it for drywall, and I discovered a crack in the wall going from one end of the basement wall to the other. The crack is no wider than 1/4 inch at its worst point, but the wall has also buckled in a little. It has been suggested to do the "French drain" as well as filling in the cracks and straightening the wall. This would include digging down to the footer. Another suggestion was to install a multi-stage system that would include an exterior stability and drainage system, repair and re-pack footings and drainage, and finally install a pressure relief system. It has been quoted just a little over 1000 dollars more than the other estimates I have received, but it seems to cover all of the problems. It comes with an unlimited lifetime warranty on all work done. Please advise.
Stop! don't proceed until you get some better answers from people who know what they are doing and have seen this situation. Here are a few of my concerns:
Where is the crack in the wall? If it is at the junction between the floor and the foundation then having a crack the length of the basement might not be a problem. If the crack is horizontal and in the middle of the wall, then it could be serious.
I don't know what you mean when you say that the wall has "buckled." Is the wall moving inward? If it is, you need a consultation from a structural engineer.
How is your contractor proposing to "straighten" the wall, what is this multi-stage system? etc.
Last but not least, I don't trust drainage work with "an unlimited lifetime warranty on all work done".
At this point I can't tell if you need any corrective work, or if the foundation of the house needs to be rebuilt. I am quite sure that you need a better analysis of the situation, preferable by and independent consultant.