Jeffreys anwser covers the business side quite well and there isn't much to add to this solid answer, but I would like to provide an answer on a more emotional level towards the deceased and their family.
I can definitely understand (been in a similar situation about 6 years ago) that you have certain sentitments towards that very much liked and valued teammember after 3 years working with him and that you and/or the team feel the need to express those while not being too intrusive.
Attending the funeral is a bit much and would be seen as intrusive by other family members or close friends who might not even know you or the other team-members, but a personal, handwritten condolence letter from the team to the family would be a resonable and appriciated reaction:
[enter name here] was a great team member and much valued and appreciated by me as well as many others in the team. ..
You can mention special qualities of the deceased, recall good memories you have of the person, remind the bereaved of their personal strengths. You could also offer help, but be specific. End with a word or phrase of sympathy for the ones who are left behind mourning.