The IRS cannot come into your private space on their own and seize business assets or your valuable personal possessions. They first need either:
(1) Your permission or
(2) A writ of entry from a federal judge.
This is a basic Fourth Amendment protection against unreasonable searches and seizures.
The IRS can enter upon public areas to take your property without your consent or a court ordered writ of entry. This means that if you car is parked at work or on your driveway, the IRS can get to it without consent or court process. In contrast, if the car is in your garage, the IRS would need your consent to go into the garage or a writ to enter.
Your consent or court order is necessary for the IRS to enter and seize personal property in areas where there is an expectation of privacy. You do not have to let the IRS in if is not in your best interest.