AI Receptionist vs Custom AI Build: The Cost Ceiling.

Answering the phone is a solved commodity, sold at a published price, and for many businesses it is the correct purchase.

Smith.ai publishes its full schedule on its own site, which is rarer than it sounds. Across the 32 vendors in our August 2026 pricing pass, only nine publish a usable rate card. In legal, two of eleven do, and of the six legal-AI tools we checked, not one publishes a price. In insurance, zero of five publish anything.

The terms are low-risk too. The published AI tier starts free at 25 calls a month with $3.00 per call after, so you can find out whether AI answering works on your own callers for nothing. Above that it is $150 a month covering 75 to 300 calls at about $2.00 a call, and $500 a month covering 300 to 1,000-plus calls at about $1.67. No setup fees, month to month, 30-day money-back guarantee.

Coverage is what you are buying, and it is worth buying. If the whole problem is that the call arriving at 7:40 on a Tuesday reaches voicemail and nobody writes down what was said, a subscription solves it this week. Nothing below argues otherwise.

Comparing a meter against a one-time fee needs a volume. Ours is 500 inbound calls a month, which is a 20-attorney firm with a real intake load or a multi-location operator running one number. The volume is our assumption. Every rate applied to it is published by the vendor.

Pro is the row that matters, because it is the plan a firm at this volume would be on. Answering the phone, one line item from one vendor, runs $45,600 a year and crosses the floor of our commission band inside twelve months.

The ceiling is not voice quality; the models under these products are broadly comparable. The ceiling is what the meter is willing to price, and a rate card is an honest description of a product's boundaries: whatever is on the add-on menu is a capability, and whatever is not is not for sale at any volume.

That last row is a disclosure gap, not an accusation. We looked twice and found no public statement about who owns the call recordings, whether transcripts train anything, or how you would export your intake history. Plenty of vendors in the same pass do publish those terms. The fix is cheap: ask for the clauses in writing before the workflow is built around the product.

The conflicts row is the deepest of those gaps, and it is a build rather than a purchase: it reads your own matter and party records, applies your firm's rule about what counts as a conflict, and has to be auditable afterwards. That build, and the six steps between a caller saying yes and a matter number existing, are worked through in law firm intake and conflicts automation.

Then there is the second contract. The record your intake creates lands in a practice management system with terms of its own. MyCase gives the firm ownership, a documented download path and a 30-day read-only window after cancellation, and separately reserves a perpetual license for aggregated, anonymized versions. Filevine's terms say the company "may, but is not obligated to, delete" your content after termination. Clio returned 403 on every path we tested across six attempts, so neither its price nor its terms could be read directly.

On the other metered vendor: Dialzara bills per minute across four published inbound tiers rather than per call, so a head-to-head would need an average call length nobody publishes. Our record for it is incomplete as well: rates captured, terms and check date not, so we are not printing its figures until it is re-checked.

Most operators who read this page should keep the subscription, and we would rather write that here than have you find it out after signing.

Small shops, plainly. A 15-user home services business on Jobber's published Grow tier, prepaid annual, with all three published add-ons including its $29 a month receptionist, pays $5,724 a year, or $477 a month. Against a $45,000 commission the crossover lands in month 95, just under eight years, and five years of that stack costs $28,620, which is $16,380 less than our smallest commission with no stewardship at all. Selling that operator a build as subscription savings would be false.

Solo and low volume. The AI tier is free at 25 calls a month. If your answering bill is smaller than an hour of your billable rate, stop optimizing it and go sell something.

Lean stacks generally. A 25-person CPA firm on the cheapest published tiers of two workflow tools, Karbon Team at $59 and Jetpack Workflow Starter at $40 per user per month, pays $29,700 a year, or $148,500 over five years. A $180,000 build loses that outright, even with zero stewardship.

Sequencing. Our most common diagnosis-call advice. Buy the subscription, run it two quarters, and let it tell you where the ceiling is: your real call volume, which conversations the product handles cleanly, and which handoffs it cannot make. That list is the scope document for a build, produced for a few hundred dollars a month instead of a discovery phase.

The logic is yours. The qualification rules that decide which caller is transferred immediately, the conflict check that runs before a matter opens, the objection handling your best intake person developed over a decade: inside a subscription those are configuration in someone else's platform, under terms that vendor has not published. In a commission they are code, prompts and models you own at handoff, running in your own Azure, AWS or Google tenant.

It writes into the stack you already run. Not a summary arriving as a record, but the conversation checking whether this caller is an existing matter or service address, applying the rule that a commercial account routes differently from a residential one, writing the fields your intake team would have typed, and triggering the next step. That is logic rather than a connector, and logic specific to your business is what a horizontal product cannot ship.

The meter stops. A fixed fee does not double when call volume doubles, which moves answering out of the cost-of-growth column.

Our terms are published rather than described: $45,000 to $180,000 fixed against a written scope, in two installments, one at production-build start and one at handoff, with the code owned by the operator at handoff. Stewardship is then optional at $4,000 or $9,000 a quarter, or nothing, cancellable on 30 days' notice. It is on the pricing page, and the sequence is on how we work.

What we can point at rather than describe: 40-plus commissions shipped, and a named legal client, Jim Glaser Law, running five channel-specific voice agents that have taken 3,787 calls across 5,514 minutes, with per-channel attribution on answered calls. Jimmy takes reference calls. Across the deployed voice work, systems built here have handled more than 6,000 live calls. The fastest diligence is to call (617) 675-9067 and talk to the agent on our own inbound line. We publish no answer rate or containment percentage beside those numbers, because we have not measured them in a way we would defend under questioning.

Related reading.

Vertical versions of this decision: law firms, home services, insurance agencies, accounting firms. The category-fit version, five tests rather than arithmetic, is off-the-shelf AI against a custom commission. Neighbours: ServiceTitan Pro against a custom build, Clio Duo against a custom AI build, what custom AI development costs, and the comparisons hub. If you are shortlisting outside help rather than a product, the twelve firms we compared are in best AI consultants for law firms.