It was done with the help of an integrator. The in-house team was also there. We had a team of 18 to 20 people for deployment and maintenance. One person is the project lead; there is a technical lead, two solution specialists, and one program manager; the rest are developers. 

We implemented the solution in-house without any vendor team involement

We have a team of three people who maintain this solution. They handle other products and there is some development, as well. If their only task was support then I think that a team of two people would suffice.

We implemented it with our in-house team.