I am considering purchasing a house, I am concerned whether some issues with the attached garage could affect the foundation of the main dwelling.

The garage is roughly 12 x 24, there is a crack that works it's way entirely across the 12' width. I am going to guess that it is caused by the 50' tree that's 7 or 8' away from the garage. The concrete is about 1" higher on one side of the crack (we'll call this side A) than the other side of the crack (side B). On side A, the concrete then angles down. As the concrete angles down it might actually be lower than originally set by the point where it reaches the wall. Side B seems to be relatively level.

On the exterior, I don't see any obvious signs of damage other than some vertical cracks in the foundation that have been patched.

The garage is attached to the house and in fact there is a portion of the house built over-top of the garage. For this reason, I am concerned whether the floor may affect the foundation of the house.

So 3 basic questions:

1) Am I being stupid by even considering this house? Would most people just rule it out automatically?

2) Assuming the foundation is sound, any ballpark idea of what it might cost to redo the garage floor? Like would I be closer to $1k, $5k , $10k, $20k?

3) Is the potential damage to the foundation something a home inspector would be provide a reasonable opinion on, or is the damage to the foundation "unknowable"? Would I need someore more specialized than a standard home inspector (say a structural engineer) to provide an opinion?