Usually yes if there is eighteen months or more before a sale, because registration widens the buyer pool. It is usually not worth starting if the sale is imminent, since a brand-new certificate carries little weight.
More detail
Certification does two things for a valuation. It removes a screening filter: some strategic and platform buyers will not look at a supplier without it, so the absence costs bidders rather than dollars directly. And it signals process discipline, which reduces the perceived risk of the earnings. Both effects depend on the system being real. A registration obtained quickly to dress up a sale is visible during a plant tour and in the audit history, and it can do more harm than good by suggesting the seller manages for appearances. Where there is time, the better project is usually to formalize the systems the company already uses well and then certify against them.