The first step in any conversion is to list what you want the conversion to do. How will you use it and in what climate conditions. Everyone has different needs so one design does not work for everyone. Consider number of people, seating requirements, where you will camp, cooking requirements, heating requirements, shower requirement, haul bikes or motorcycles inside, can a tall person sleep across back of van, etc. Once the requirements are listed then different layouts can be tested. Each will have positives and negatives. Suggest doing the layouts to scale. Easy to go to a dealer and measure vans to determine the space available in different models. One approach is to do a full size layout on a garage floor and built it with sticks and cardboard. Move stuff until you find the best layout. I knew CAD design from my busines so used accurate scale drawings to design the layout.
Once you have determined what you want the conversion to do and have decided on a floor plan then you can purchase the vehicle. What you buy and what options are ordered depends on your layout and how you will use the conversion. Since you will pay $40,000 plus for a new van and are likely to keep it for a long time, I would order a van instead of buying a van off a lot that does not have the options that you want. The delay is worth it. Spend time reviewing every option to see if it fits your intended use. The van length is a important decision. Short to use city parking easily or longer to give more interior space. A longer van may be a requirement if one of the users is too tall to sleep across the back of the van. I found in the Sprinter conversion that it is not comfortable to sleep slightly diagonal.
Both the Sprinter and Transit conversions cost about $20,000 for materials and took several years to build. Do you have the time, a place, tools and skill set to build your own? If not, then a used or new conversion might be a better choice. I did enjoy the designing and building process and learning new skills. It is both easier and harder to do a second build. Easier because you have experience and can refine the build but much harder because you know how much time it takes. It will take at least 4 times longer to build than you think it will.
For us the object of our build was to construct a travel vehicle that is stealth and can be used to city camp. Wanted it to fit normal parking places. Van needed to be self contained with utilities and not require RV park connections. Lots of thought went into how our needs would be met. We will not have exposure to extreme temperatures very often so did not design for that. Wanting to be as stealth as possible eliminated things like bicycles hanging off the back, an awning, obvious window coverings, visible utility connections, etc. Van needed to look like a tradesman vehicle from the outside. We only needed accomodations for two people and we could sleep across back of van if care was taken on the bed design. We did want to have a table where two people could eat or play cards. Counter space is a problem in a small conversion. Using a portable gas stove provides additional counter space. Did not want a built in stove because we wanted flexibility on cooking location. Did add additional counter space by adding a counter height shelf in the shower enclosure.
Prefer simplicity over complex with regards to utilities. Shower water is heated in an open tank, sink water uses a small solar centrifugal pump operated with a switch. No hot water at the sink. No generator or central heating. Have vehicle powered inverter to use Transit gas engine as a generator. Use Transit engine and the inverter powered electric heater to heat the van in the morning. Let van interior get cold at night and use a 12 volt heating pad to stay warm.
Electrical system is different than most RV designs. We have two pure sine inverters. One powered by the vehicle 12 volt system and one powered by the house battery.
Since space is limited, the interior cabinets and bed platform are designed for multiple purposes. The bed platform can be converted to a table for two. The shower enclosure includes the portapotti, shower water tank, two storage containers, an additional counter and two removable/pivoting shelves so space is used for more than a shower. Parts are removed to create a shower or use the portapotti.
The interior is constructed using 80/20 extrusions. 80/20 makes it easy to build and fit my skill level. All the cabinets are bolted together to create one large structure in the van.
Use the menu at the left to view information about each part of the build.