Ask what problem the installation is solving
Do you need better room coverage, a better way to control access, easier resident payments, more reliable equipment, or all of these together?
A useful installation plan should match the real problem. Buying equipment without answering this question can leave you with the same complaints in a new form.
Ask how the service will be managed afterwards
The work does not end when devices are installed. Residents still need to connect, pay where needed, renew access, report problems and understand what to do when something changes.
Before paying for hostel Wi-Fi, ask who will handle those day-to-day parts of the service.
Ask what you will be able to see
If internet matters to your hostel, you should not be blind after installation. Ask whether you will be able to see network status, resident activity and earnings where residents pay for access.