Angela, it’s over 10 years old, that should keep the cost down by 50%, it did when I registered my just 10 yr old UK bought Clio in 2008. My old neighbour told me 4 years ago, the Herault department was the most expensive dept for getting a Carte Grise!
But does yours need reregistering just for changing depts., thought that law was changed when they brought out the new style plates. Dept No. gave a sense of identity and many French residents clamoured to be able to keep that option. You may not need to change the plates, possibly just let the police / prefecture know you are now the owner, but I’m sure the gents on here will know better than me! Re Insurance, I used AXA, speak to the AXA ladies who advertise on SFN, they speak English and one of them is.