Building a motorhome is a lot cheaper than purchasing one which can be expensive and often filled with unnecessary extras. Turning a van into a motorhome requires a little thought, lots of work and far less money than buying a prebuilt motorhome. Custom designed by you and purpose built, building your own motorhome is a rewarding and money saving project.
Acquire a van designed for commercial use, such as a delivery van. The less there is in the back of the van the better. For larger needs consider a retired school bus and account for the potential space needs you require.
Select your water storage system and consider how you'll use it. If it's for simple cooking and cleaning needs, you may be able to use a 5 gallon water storage and skip running basic plumbing. Showers and running water require considerably more water; install the water tanks before the interior build takes place.
Assemble your motorhome based on your careful design. Expect to make small modifications in order for everything to mount correctly. Hire an expert to assist in areas you're uncomfortable working and test everything carefully prior to hitting the road for the first time.