You could have 1 truck for 50 houses and it would sit unused most of the time.

My local Uhaul does a pretty brisk business in a neighborhood of 150 houses, and they've got way more than three trucks.

Most people need their trucks to move and maybe a few times a year to haul stuff from home depot.

There's definitely peaks and troughs. Everyone likes having a truck when its time to pick up a Christmas Tree or re-sod the yard. So you run into a problem of people having one week where nobody needs the truck and one week where everyone needs it.

But also, having a "community truck" opens the opportunity for other community projects. Would be nice if the truck came paired with a few professional construction workers who could direct a community effort to update the local playground or fill potholes or do more advanced home repairs (roofing / re-siding, etc). Then we start talking more broadly about a Citizen Conservation Corps or similar public works department that exists to create/upgrade/maintain amenities across town without getting price-gouged by for-profit contractors for the privilege.