Start with the work you actually need
List recurring requests, unresolved issues and planned improvements. Separate day-to-day user support from development, integration and architecture needs. A provider should be able to explain which work it can handle and where another specialist would be required.
Ask how requests become scoped work
Find out how a request is submitted, who clarifies it and how effort is agreed. Ask what happens when a simple question turns into a larger change. Discuss response expectations explicitly rather than assuming that a support agreement includes a particular response time.
Compare the full commercial arrangement
Review the rate, any minimums or prepaid hours, how time is tracked and how additional work is authorized. A lower rate is only one part of value; consider the relevance of the expertise, the clarity of communication and the amount of rework.
Use a real task to evaluate the relationship
Choose a bounded piece of work with a clear business purpose and agreed acceptance criteria. Observe the questions asked, the communication during the work and the quality of the handoff. Avoid using an urgent, business-critical change as an unplanned trial.
Prepare for a clean transition
Before replacing a provider, confirm ownership of custom code, documentation, integration accounts and outstanding requests. Agree on access changes and the handover process so important context is not lost.