Hi fellow adventure alternative travellers!

My husband and I are planning to leave our London jobs and fulfill our dream of adventure, exploration, sharing, learning and understanding of the world. We are looking into caravanning through parts of Eurasia, South Asia and crossing to South America and upwards, thus leaving Europe out of the equation and probably keeping Africa for another trip. Stops would include Georgia, then going down to Iran, Afghanistan, Pakistan, India, Nepal, China (Bhutan and Myanmar if possible), Thailand, Laos, VietNam, Cambodia, Indonesia, Philippines, New Zealand and crossing the Pacific to reach South America and travelling up to reach Canada. We have friends along the way where we can stop and replenish if necessary.
It seems we still have to sort out quite a few things like laws and technicalities regarding crossing borders, knowing how to sort out mechanics, contacting newspapers, blogs and other editing companies to partly fund this challenging trip, finding the caravan itself and preparing to leave the country. We are also looking into funding this experimental year-travel in various ways such as travel writing, teaching, development work and along the way jobs if necessary.

We would be very grateful to read your comments an sugestions as we want to become more knowledgeable and mindful to prepare this journey.
- Has anyone done it before?
- Where to buy the caravan, or if it is feasible to buy it in Georgia or India?
- Best ways to reach Indonesia-Philippines-New Zealand? And crossing the Pacific?
- Culture shocks we should be aware of when travelling by caravan?
- Restrictions when travelling by caravan, in terms of getting to places for example?
- Costs, restrictions and practicalities generally
- Words of wisdom and encouragement!

Many thanks in advance for your contributions.