What actually stops the 2am "the site is broken" calls after a client handoff?

Instrument it so you find out first.

An uptime check on the main pages and error alerting on the backend costs very little and changes the entire dynamic of the call. "I saw it go down eleven minutes ago and it is already back" and "you are telling me it has been down all day" are two different relationships with the same client.

It does not reduce call volume much on its own. It changes what those calls cost you in trust, which is arguably the more expensive currency.

A five-minute screen recording, sent as a link, beats any document I have ever written.

Clients will watch a video. They will not read a PDF. After I started sending one, the questions that survived were overwhelmingly actual bugs rather than "where do I click", which is the split you are describing.

Two details that matter. Record it in their own data, not a demo account, so they recognise the screens. And keep it under six minutes — the moment it becomes a training course, it goes in the same drawer as the document.

Look at your one-in-six number again. Most of the other five are billing and ownership, not code, and that is fixable with an afternoon of admin.

One page listing every account in the stack — registrar, DNS, hosting, email, payment processor, any paid plugin or API — and for each one: who owns it, which card it bills to, when it renews, and what breaks if it lapses.

Then the part people skip: during the handover call, while you are both on the line, put the renewal dates into THEIR calendar. Not yours, not a shared document. Their calendar, with a reminder two weeks ahead. An expired card is a Tuesday-afternoon problem if it is on a calendar and a 2am emergency if it is not.

Half of this is a contract problem wearing a documentation hat.

Define the support window, the response times, and what counts as an emergency, in writing, at signature. Not after launch, when you are negotiating from a position of guilt and they have already formed the habit of ringing you.

The reason 2am calls happen is that 2am calls are free. Documentation reduces how often somebody needs you. Only the agreement changes when they feel entitled to reach you.

Give them one URL that answers "is it me or is it them".

A good chunk of the 2am calls are the client's own broadband, their own laptop, or a captive portal in a hotel. A trivially simple status page — even one static page hosted somewhere entirely separate from the app — lets them check before they dial. Put the URL on the one-pager and say it out loud on the handover call: "before you ring me, load this."

It filters a surprising number of incidents that were never incidents.

Put everything in a shared workspace — wiki pages, credentials, runbooks. That is what those tools are for, and then it is all in one searchable place.