Self-proving affidavit
A notarized affidavit signed by the testator and witnesses at execution lets the will be admitted without tracking down witnesses years later. Its absence means someone has to locate and depose them.
A contested will, an unsigned original, out-of-state land, creditor claims, or a filing threshold: what to look for before you commit to handling a probate alone.

One estate, three fee agreements read closely before any of them was signed, and what the differences between them turned out to mean. Written for the person deciding how much of a probate to hand over and how much to keep.
The cost of an attorney in a probate is not fixed at the moment you hire one. It moves according to what has already happened, and the most expensive engagements tend to begin after an executor has spent four months doing something that must now be undone: a distribution made early, a house listed without authority, a claim paid out of order. Reading the file carefully in the first two weeks, before any deadline forces a decision, is the cheapest work anyone will do on the estate. Here is what a careful reader looks for.
Start with the physical document, not the copy the family emailed around. Check for the testator's signature, the witnesses' signatures, the date, and whether a self-proving affidavit is attached and notarized. A photocopy is not the same as the original, and in most states an original that cannot be produced raises a presumption that the testator destroyed it, which is rebuttable but not by an executor working alone. If what you are holding is unsigned, unwitnessed, or a scan of something nobody can locate, that is the point to call, before the petition is filed rather than after it is denied.
The same applies to a will with visible interlineations, a page in different type, or a codicil referencing an instrument you have not seen. None of these is fatal. All of them are cheaper to address in a first meeting than in a response to an objection.
Contests rarely arrive as a surprise. They are usually preceded by a phone call, an email about the last-minute change to the residuary clause, or a sibling who has asked to see the drafting attorney's file. Take that seriously the first time it happens. Once a caveat or objection is on the docket, the estate is in litigation, and litigation is billed hourly by nearly everyone who does it, on a schedule the executor no longer controls. Counsel retained early can often narrow the dispute with a settlement agreement among the beneficiaries, which is a document, not a trial.
Look at the deeds, and look at where the land is, not where the decedent lived. A cabin in another state, a rental across a river, an inherited mineral interest two states away: each generally requires an ancillary proceeding in the county where the property sits, with its own filing, its own local counsel, and its own timeline. Executors who discover this in month seven, after the buyer's title company refuses to close, pay for speed. Executors who find it in week two can open both proceedings on the same schedule and often sell without a gap.
Add up what is liquid, meaning bank accounts and marketable securities payable to the estate rather than to a named beneficiary, then add up the claims: the credit cards, the final medical bills, the mortgage, any Medicaid estate recovery notice. If claims plausibly exceed liquid assets, the estate may be insolvent, and every state sets a statutory order of payment that an executor who pays the sympathetic creditor first can be held personally liable for ignoring. The related check is the loan nobody documented. When a beneficiary also owes the estate money, that balance usually has to be accounted for against their share, and the conversation goes better with an attorney in it.
The Internal Revenue Service administers the federal estate tax and the return that reports it, and the threshold is indexed, which means it changes. Do the arithmetic on gross value: real estate at date-of-death value, retirement accounts, life insurance the decedent owned, business interests, and any lifetime gifts that used up exclusion. Then check the state, because several impose their own estate or inheritance tax at a far lower number than the federal one, and a surviving spouse who wants portability of the unused federal exclusion has to file a return to elect it even when no tax is owed. That deadline is nine months, extendable. It is not a thing to discover late.
None of these six is a reason to hand over the whole estate. They are reasons to buy an hour, get the shape of the problem, and then decide how much of the remaining work you keep.