Sounds like an old, make it work job.
You may need to support it with the help of a professional. Unfortunately there are no easy, cheap fixes for something like the foundation structure you are describing. Sounds like this is what happened in the first place to get you into this mess.
Get yourself a home inspection before you finalize your offer .
for a competent inspector. This is a professional organization, not a company.
Hope it works out for you, sometimes it is easier to start fresh with something like a garage.