The choice to live full-time out of a vehicle seemed like it was pretty easy compared to deciding, once we were settled on doing a stint of road life, which vehicle to choose. We did tons of research and a lot of pondering before we settled on a shuttle bus, and while our choice wouldn't be right for everyone, we wanted to lay out our thinking in case anyone else is going through the same process.
Our criteria: we wanted something reliable and safe, something in which we could stand up, and something with enough space to feel livable for a family of four.
Initially, we were most attracted to vans. We liked the stealth, the gas mileage, and the safety, and there are so many resources for van conversions that we were confident the project was doable. We thought we'd go that route and spent most of our time considering whether a Sprinter or Ford Transit would be best. But in our configuring, we just kept running into problems. The biggest Transit was too small. The Sprinters were a good size, but we weren't thrilled about getting into a Mercedes: we have family members who own FedEx routes and fleets of Sprinters and they unilaterally described Sprinters as problem vehicles. It seems that once Sprinters get a good bit of mileage on them, they start having a lot of engine problems, and because they're Mercedes, the problems are super expensive to fix. While we know plenty of people who love their Sprinters, we didn't want to get into something that would be so potentially problematic.
We also looked at installing extended fiberglass tops to other types of vans in an attempt to get the Sprinter height with the reliability of another vehicle. But other vans had shorter wheel bases, which meant much less living space.
So we started looking at RVs. They seemed like an obvious choice and still, when we showed people what we were planning with the bus, we were invariably asked some variation of, "So why didn't you just buy an RV?"
Well, for a few reasons. Safety was a big one, especially with the kids. While buses are basically constructed inside a metal cage, RVs are much lighter and less rugged. The kids' seats would probably have been hooked to dinette seats, which vary in their construction, but are frequently much less sturdy than typical car seats. We're not planning on getting into any fiery crashes, but if we did, we want something that will hold up. I definitely don't think an RV is an irresponsible choice. But knowing how much time we'd be spending on the road, we wanted to be really comfortable with our level of safety.
We also had a hard time finding an RV layout that made sense for us. We wanted to sleep in the same area as the kids, but probably not the same bed (because we are all giants and sloppy sleepers), which we couldn't configure in an existing RV layout. We wanted to be able to work comfortably after the kids went to sleep. And we really didn't want a bathroom, so we were hesitant to sacrifice space to one. It might seem odd that a bathroom was on our list of undesirables, but we didn't want to deal with a black water tank or a frustratingly tiny sink, and we definitely didn't want an RV shower. When you are 6 feet and over, RV showers are just a special kind of cruel. (But all this about the bathroom would likely be totally different for someone else. I have strong, experience-borne aversions to RV bathrooms that a lot of others don't share. So take it all with a grain of salt.) We also wanted solar power, good insulation, and a full-sized sink, along with a bunch of other features that weren't totally crucial, but would make it more livable for us.
Basically, we knew if we got an RV we'd have to gut it to get a layout we were really happy with, and if we settled on a layout we didn't love, we'd still want to add enough upgrades that it didn't seem to make sense to invest in an RV in the first place.
So we were down to buses.
We honestly never considered a school bus because as soon as we started looking at buses, we found a wholesale dealer in Arizona and immediately connected about a couple of shuttle bus gems, including the one we ended up with. School bus conversions look awesome, but we think it would have been a poor choice for us, mostly for time reasons. We had to get our build done in a little over a month and a school bus conversion, because they usually involve grinding out rust, raising the ceiling, and other metal work, would have taken much more time than we had.
So all in all, we are super happy we ended up where we did! The shuttle bus isn't perfect, of course, but we loved being able to design and build it to fit our little family. And now that we've been in it full-time for several months, we can honestly say that the choice has been perfect for us.
We hope this helps, in case you're considering the bus/van/RV-life for yourself! If you have any questions, let us know! We're not experts, but we'd love to share our experience.