I hired a contractor to do some work n my house, I signed his contract. He sub contracted the work to someone elase, they did it wrong according to the City Inspector, My contractor fired them, and is having someone else finish the work. Can the original sub contractor sue me for the money he is owed? or put a lein on my house?
Theoretically the sub can file both a lawsuit and lien (presuming the sub meets all of the legal requirements). The sub's case would be "stronger" with a written contract, but the Sub can make an unjust enrichment claim or similar claims.
Your protection comes from not paying the contractor until you are provided a release of lien from all subs and suppliers used on the job.