If I'm getting a check make payable to my father's estate and I haven't opened acct yet how can I cash it

Please accept my condolences on the loss of your father. As for your question, something is odd about what you are saying you've been told. If the property was owned by your father when he died, then either (1) the title to the property is still in his estate, because he was either the sole owner or he owned his interest in the property with other owners, but as tenants in common, or (2) the title to the property actually belongs to other people already, and no part of it is in his estate, either because he and the other owners held the property as joint tenants with rights of survivorship or because he died without any valid Will in place and the property passed to his heirs at his death under Georgia law, subject to being pulled back into his estate by the appointment of an administrator. If your father's interest in the property did not pass automatically to you and your brother as surviving joint tenants, then you and your brother should not be able to sell the property at all until his estate is opened, UNLESS you are selling it as his only heirs, he had no Will, and his estate has not been opened for administration. However, in that case, the check should be made out directly to the two of you, not to your father's estate. If you are being told that the check should be made to the estate, and the estate has not been opened yet, you should not be able to even sell the property until the estate has been opened. You need to hire a probate attorney who can sit down and actually review all of the relevant facts of the situation and guide you on what to do and what to tell the person who is trying to make out the check. If you need to open the estate, the probate attorney can help with that. If you and your brother really don't need to open the estate, then the probate attorney may be able to help you explain that to the real estate attorney and get the check made out directly to you. This kind of forum does not allow anyone to provide you with that kind of situation-specific legal advice, however. Best wishes to you.

You cannot cash it until you open the account.  Nor can you legally sell the house until a court appoints you executor (if there is a Will) or administrator (if not).  Contact a local probate attorney.