hi there as i used to underwrite some policies in car finance i know a little,

you should grab your documents out and have a look to see if the agreements show any information about voluntary termination, basicly what that is providing the agreement is half way through, and you have been good with your payments then you can return the car to them and you nothing, because this car is their property until you finish paying it. you have to write to them (make sure you keep a copy and recorded post) to say you would like to return the vehicle to them under the section of voluntary termination. this is a right which will state in the agreement,

i know you have missed 1 payment but it will depend whether if they will accept it, if it doesnt say anything about late payments in the voluntary termination then you should be ok.

what they will do is ring you and arrange something so they will come and collect car, once they have then you have nothing to owe on it.

as far as the credit profile side of things, it will say settled however it will point out voluntary termination so in the future if you get car finance perhaps some finance companies will decline you because you have a habit of this or they will still continue.

hope this helps a little