I'm possibly in the market to upgrade my service truck. Right now I have a service body Chevy 2500. It works well except the bed is exposed and there isn't proper space to stock any parts. I am looking at possibly a used sprinter. I like the new ones, but $40,000.00, yikes. I also see some guys are using UHaul trucks with the 10' box. I like this idea except the climbing in and out.
I do mostly service work with a new house here and there(actually I have 3 in a row starting Monday, one of them 5k sf).
My gambit has been to use sideways Knaak boxes -- mounted directly to my service body.
Because the expense for a Sprinter -- or anything like it -- is so high -- I favor using a (covered) trailer, instead.
It's only brought into play during a serious build.
The extremely low height available with a trailer is a real step saver.
Wander over to Ask This Old House -- see YouTube -- or This Old House -- to see what Tommy Silva has rigged up. His trick trailer has a collapseable suspension that puts the floor all the way down to the ground.
You will find that climibing in and out of a Sprinter is brutal on your knees during a build. The other advantage is that you can take off for mid-day materials -- while leaving your crew enough (protected) supplies to keep on building.
In many areas, leaving materials out -- even during the work day -- is an invitation for theft.
As for the trailer: have it rigged with a natural skylight for internal illumination (like a UPS van) -- and PV panels, too. These make it possible to top up your battery packs in a secure environment -- and impossible to forget at the end of the day.
For service calls, you fall back on Plan A: just the service truck.
BTW, ladder racks are staggering fuel pigs; figure on a 20% bump in fuel expense when hauling them around. Ladders toted inside a trailer travel pretty much free.
PV arrays provide enough energy to drive LED signage and spot interior illumination... and a security system!
Hence, you're showcasing an item that you'd love to sell and install.
Guys up here run Sprinters, Box trucks, utility body (side bins),350 Ford type vans, the newer 'Transit' rigs.
Two have trailers as Tesla touted. Great to leave at a site. One has PV panels with micro inverters for 120 v. A secondary trailer is a tilt bed that he can get his scissor lift, power benders, gang boxes into easy. He also has a stake body trailer that he hauls 'scrap' for the $$$$.
When I had my business, I had Ford 350 vans, a utility body (Enclosed) with side bins, and a 55' Teco bucket w/a utility body.
Bottom line is how big is your budget, anddo you want 'new' or previously owned (certified)??
A good place to scout 'used; is "The Electrical Advertiser"
Had to beat a cargo van. I'm currently using a 2012 one ton cargo van and has done me good so far. You may not need the one ton chassis but I did and it has been used several times for large capacity batteries and packed to the gills with big spools of wire and such