Scope exclusions in writing
The value of a flat fee lives entirely in the list of work it excludes. Ask for the excluded items to be priced at the time of signing rather than when they arise.
Flat fee, hourly, and statutory percentage quotes are priced on different bases, and a careful reader checks what each one counts before comparing the numbers.

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 three fee agreements that arrive after an executor calls around are usually priced on three different bases, which is why the numbers so rarely line up. One quotes a single figure for the whole administration, one quotes a rate per hour with no ceiling, and one quotes a share of the estate calculated from a statutory schedule. A careful reader stops before comparing the totals and works out what each agreement is actually counting, because the base matters more than the headline. On the same estate, the same lawyer can produce three very different bills.
A flat fee promises a defined scope, and the scope is where the work is. Read the agreement for what falls inside it: the petition, notice to creditors, the inventory, the final accounting, the order of distribution. Then read for what falls outside, which is commonly litigation, a contested claim, the sale of real property, an ancillary proceeding in another state, or a federal estate tax return. Flat fees are predictable and easy to budget, and they are honest about scope when the exclusions are written down plainly rather than gestured at. Ask for the excluded work to be priced now, not later.
Hourly billing promises that you pay for what is done and nothing more, which is genuinely valuable on an estate that turns out to be simple. What a careful reader checks is the machinery around the rate: who else bills, at what rate, in what increments, and whether paralegal time is billed separately or absorbed. Six-minute increments behave differently from quarter-hour increments over hundreds of entries. Ask whether the firm will provide a written estimate with a range, whether it will notify you before crossing a threshold, and what the invoices will show line by line.
A minority of states still publish a fee schedule for probate work, and California is the best known of them, with a graduated percentage applied to the value of the estate accounted for. Several other states, among them Iowa, Missouri, Montana, Arkansas, and Wyoming, set percentage schedules or statutory maximums in some form, and Florida law identifies a presumptively reasonable fee by tiers. The distinction that matters is whether the schedule sets a ceiling, a starting point, or a default the court will approve without much inquiry. In most states there is no schedule at all, and reasonableness is judged case by case.
Where a schedule exists, it usually applies to ordinary administration, and anything characterized as extraordinary is billed on top, subject to court approval. Selling the house, defending a will contest, running a business through the administration, or handling a tax controversy are the familiar examples. So a percentage quote in a schedule state is not a cap on your total cost; it is a cap on one category of it. Ask which tasks the lawyer expects to petition for as extraordinary, and roughly what those petitions have come to on comparable estates.
Percentage fees are almost always computed on gross value, not on what the family will end up with. A house worth six hundred thousand dollars with a mortgage of five hundred thousand counts as six hundred thousand for fee purposes, which means the fee is calculated against equity you do not have. Debts, liens, funeral costs, and administration expenses do not come off the base. What does often fall outside it is everything that avoids probate: a funded revocable trust, joint accounts with survivorship, retirement accounts and life insurance with named beneficiaries, and transfer-on-death registrations. A careful reader asks for the fee base in writing, itemized asset by asset.
Build a single scenario and price all three against it: this inventory, this house with this mortgage, one creditor claim, a sale of the residence, a final income tax return for the decedent, and no litigation. Ask each firm for a dollar figure or a tight range on those facts, plus the cost of the two most likely surprises. Add the court filing fees, publication, appraiser or probate referee charges, and bond premium separately, since none of those belong to the lawyer. Note also whether an estate tax return is even required, a threshold the IRS is responsible for, because that single filing can move a quote substantially.
Then ask each of them the same closing question: what would have to happen for this bill to double, and would you tell me before it did. The answers separate the agreements faster than the prices do.