Good luck. Those are, largely, mutually exclusive desires.
Keep in mind appraising is an art, not a science. Valuing real estate today is challenging. Did an estate return where DOD in July 2006 resulted in an appraised value of 726,000 for decedent's home. Executrix just got it under contract for 700,000. How do I (or should I even try) to convince the state that the estate overpaid its tax and is entitled to a reduction. I don't think it'll fly in today's crash & burn real estate climate. Two years is likely to be deemed too long, given the unique real estate market decline.

Overvaluation can cost the estate more in taxes. Undervaluation can distort beneficiarie's shares.

BTW, is the executor a relative of the decedent or an attorney or bank/trust company? Keep a close eye on family members serving. They may have their own agenda (or financial pressures).

Edit: Over the years I have concluded that the two times in a person's life his veneer gets pulled back and his soul is exposed are in a divorce or when someone dies and you are beneficiary. I've seen some really ugly stuff go down.