Probate exists to protect the estate and its beneficiaries, since it publicly confirms the will is valid and the named executor has authority to act, which title insurers and buyers' lawyers will want to see before closing on the sale.
The process typically takes 2 to 4 months depending on the estate's complexity and whether the will is contested, and a house can usually be listed for sale while probate is still in progress, but the sale cannot legally close until the grant is issued.
An executor who lists early and has the grant ready by the time an offer comes in avoids the sale stalling at the closing table. Get your hand-reviewed valuation from Joel Dyck.