Jay C Davey wrote:I have no idea of what a 4C climate is
West coast, like Washington or British Columbia.
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Both Mark and John's suggestions are good.
For anyone starting out that doesn't have building or homesteading skills, the RV is likely the better choice as it's still like living in a modern home. It tends to take more of an investment though.
If you want to try building a shed to live in, I'd suggest adding a small glass house attachment on the south side. The attachment helps create additional space to utilize while giving you the materials to use for a greenhouse later on.
Codes will be problematic, so I'd look for examples of people who have already had to find ways to deal with them in your area and copy what they do.