IRS tax liens

What happens when the IRS discovers that you bought a property at auction with a federal tax lien on it after you refurbisher it? Does anyone know the process, what items of expense the IRS will reimburse, when you will receive your purchase money, etc?

They not only have to discover it, but also exercise their right to redeem the property. If they do you can try to negotiate to get your repairs reimbursed, but it is my understanding that they don’t have any obligation to repay you for anything other than emergency repairs that were made to secure the property from damage that would have otherwise occurred (think water leak).