Whether you ship furniture will depend very much on the prices you are quoted,but I think it's likely to be cheaper and easier to sell and re-purchase in france.
Regarding the car I would recommend selling and purchasing in france , not only to avoid the cost of shipping , but also because it is very difficult to register a non-european car in france; although Nissan cars are sold in france ,they are almost certainly made to different safety specifications , and because french officialdom is addicted to paperwork you would have to obtain some kind of certificates of conformity acceptible to the licencing authorities which would almost certainly be an exhausting and expensive task-I know someone whose camping car (built in Germany!) took 2 years to be registered in france, and then for his use only and prohibited from being sold in France!
As regards shipping the personal possessions I cannot help you, I can only suggest comparing quotes.