We write to them for you, politely, with a list. Most handovers take a week (sample).
Passwords
Every admin account, the router, the firewall and the Wi-Fi
Backups
Where they are, how old the last good one is, and a copy
Licences
Which ones are yours and which are in their name
Notes
Anything unusual: old software, a special printer, the CEO’s home set-up
Book a free IT check
An engineer spends an hour at your office (or on a call) and writes down what is backed up, what is out of date and what is fine. You keep the notes, whether you sign up or not (sample).