1. What’s their reputation?

Check sites like Trustpilot and get industry references.

2. What’s their focus?

Do they specialize in the service you need or is it just one of many services they offer? Worse, is the service a sideline business?

3. Do they take ownership?

In other words, will they treat your customers like you would?

4. Do they offer private-label services?

Keep customers focused on you with a third-party that doesn’t mind doing its work behind the scenes.

5. Can they grow with you?

Ideally, you’ll be working with this partner for a long time. Are they willing and able to expand with your needs?