I bought an ecommerce store, and the pixel is very mature on FB. Over $50k spent in it. Apparently, facebook does not offer a way to 100% transfer ad account from one business manager to another. Are there any tricks to making this work? For now, I am operating with the ad account under my business manager and as the sole person with rights. However, the original owner could technically add them self at any point if they felt like it given the ad account is still associated with them.