There seems to a lot of people considering vanlife. I spent about 1.5 years traveling in my van and figured I would throw out some lessons I learned. Hopefully, they are helpful to someone considering vanlife. Also, maybe other vanlifers can throw out some lessons they've learned as well.
1. Get comfortable talking to strangers. Especially if you're traveling solo. I'm originally from Washington D.C where talking to strangers is not the norm so this was new for me. Traveling solo in the van can be lonely and isolating unless you get comfortable to intentionally making friends. I ended up making some life long friends out of people I met in a Walmart parking, a random campground, or hiking on the trail. It's especially helpful to talk with locals who will always know the best places to camp/hike/etc.
2. You don't need that much stuff. Obviously, to each their own but personally found that I didn't need that much. I didn't have a bathroom, fridge, A/C, or other amenities I've seen people put in some vans. I did a simple solar set up and bought a fancy cooler that could keep ice for multiple days. I kept it simple and was ultimately glad I did. For me, the van was just a means to get me to places that I wanted to be.
3. Be flexible. Your van might break down, the weather will ruin plans, free campsites will be full when you arrive. Stuff happens. Just be ready to change plans and see where the road takes you. If you know that when you set out you'll have a much better attitude when everything seems to be going wrong.
4. Finding a permanent place to park. This tip only applies people who want to stay in one area. For about six months in the van, I lived outside of Orlando, FL. I went on craigslist and looked under the "rooms" section within the housing section. People in this section are often property owners that are looking to rent out a room in their home. I looked at the pictures for properties with lots of land and then sent them an email explaining that I just wanted to park my van on their property. I ended up getting a lot of positive responses and found a great place to park for $50 a month.
Just my experience but hope it may be helpful to someone else!