I have two of these on the roof of my van and love them: http://www.amazon.com/HQST-Monocrystalline-Flexible-Solar-Panel/dp/B017OMTAV6
I attached them with the strongest outdoor double stick tape I could find, and ran caulk around the edges to seal it from water getting underneath.
I've read that they are having trouble with the 100 watt version, but I think the 50 watts are still being produced.
I was looking into HQST. They seem to have good reviews and they are cheaper.
Edit: Looks like Renogy sold their raw materials to HQST. I'm not sure what they did to fix the issue that Renogy had, but those who have purchased them seem happy.
Here's a list and example found on amazon for all the major parts. I'll also include a wiring diagram at the end.
Solar Panel $169.99 - 100W Flexible & Thin
Solar Cable $18.99 - 20ft with male and female heads (cut in half for + & -)
Charge Controller $34.99 - 30A gives you room to add more panels
Battery $160 - 100Ah AGM will provide enough power depending on fridge but requires no maintenance
Fuse Panel $35 - 6 circuits with negative and cover
12V Sockets $6 - Get some of these for plugging in appliances and phones. You can buy 12V adapters for almost any electronic besides most kitchen appliances.
Pick up some 10 gauge stranded wire from your local hardware store (home depot) to wire the battery and fuse panel to the charge controller. You shouldn't need much since you want the battery as close as possible to the controller. You can buy smaller wire (16 or 18 guage) for wiring outlets/appliances to the fuse panel. 50ft of that should be fine unless you want multiple outlets on the other side of the van.
You'll also need some ATC blade fuses for your fuse panel. You can buy these at a local auto parts store pretty cheap. 15 amps should be enough than anything you'll be pulling.
To connect the wire ends to the battery and fuse panel you will need these wire terminals for the corresponding wire guages you are using. Along with these female terminals to connect to the 12V sockets. All of these can be found at your local auto parts store for cheap sometimes all together in a kit.
You'll also want a pair of wire strippers/crimper for wiring.
This is the best wiring diagram I can find. Most are so overcomplicated. This diagram does not show the fuse panel but you can see the empty slots on the far right of the charge controller where you insert the wiring for that, it's called the "load." This diagram also shows an inverter which is something I didn't go into because you will only need that if you HAVE to run a 110V appliance. I know you mentioned a kettle but maybe you could just install a gas stove in your van and use that to heat water? That's what we use :) Installing the inverter should be pretty straight forward though if you need it but remember you will waste energy going from 12v to 110v so 12v is more efficient.
Hope this can help you (and maybe others) in some way. I plan on making a more in depth version of this guide in the near future along with a video but finding the time has been difficult! Let me know any more questions you have :D
Yeah, I thought anyone interested in the thread would be! But as soon as I posted the original version with amazon links, it was auto-deleted. Weird.
Oh well, here are my products:
Charge controller: https://www.amazon.com/dp/B00JMLPP12/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=3NTUA0DGQ65YX&coliid=IMF9F8IHLJ6EN&psc=1
Battery isolator: https://www.amazon.com/dp/B0058SGDFK/ref=wl_it_dp_o_pd_S_ttl?_encoding=UTF8&colid=3NTUA0DGQ65YX&coliid=I2UYT4LFVI14AN
LED lights: https://www.amazon.com/gp/product/B007JF2A6G/ref=od_aui_detailpages02?ie=UTF8&psc=1
Main line fuses (inline): https://www.amazon.com/dp/B00WZHE3A4/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=3NTUA0DGQ65YX&coliid=ICS8GYAQNUJV1&psc=1
Also, for reference these are the panels; HQST 100W Monocrystalline Solar Panel (2-Pack Solar Panels) https://www.amazon.com/dp/B017OMTAV6/ref=cm_sw_r_cp_api_glt_fabc_XP0XYHPCPEDJ94R7B2WF?_encoding=UTF8&psc=1
If money isn't a huge concern, LiFePO4 batteries might be a great option since they are much smaller and lighter. Just something for you to research/look into :)
As for panels You could probably fit 4 of these flexible panels on your roof. You can use this to calculate your needs though because how much you need depends on how much power your things will draw every day. Good luck!