" Senegal - you wont be able to enter without it. At Diama it is sold next to customs office in same shed with cocacola
Dont remember the price, but this insurance is valid in Mali and Gambia at least."
I reckon the cheapest insurance you can get for Senegal (never been) and Mali etc is actually to be bought in Mauritania. Though it's not valid in Mauritania.
Go to Auberge Sahara in Nouakchott (google their website, you will drive past them as you enter from the north on the new sealed road). Ask the owner. He will phone the bloke who is the agent who will arrive on his scooter.
It covers Mali and a whole bunch of other places (Senegal I think, but can't be sure) and is very cheap. Only about 50 euro cents a day I think rather than nearer 1 euro a day. I seem to think I paid 35 euros for 3 months?
And if you leave the sticker in place when you return to France with no assurance and are stopped at a road block where they are checking, you can confidently point to it and say "Yes, I have assurance".
It was still valid. Just not in France.
Also, keep the green Mori insurance. Leave it in the sun to fade. When you come back you might get stuck with it being a Sunday or holiday or something. So to avoid fines (they check often in Mori to try and get a 25 euro fine) just write over the top of the faded pen (at the WS/Mori border in the caravan they write in pen, in NB they used a computer maybe?) and use it until you can buy some more.
Just a couple of tips/stories I picked up. ;-)