alot of the places youll have to take a 10/12 mnth policy out, normally this requires a deposit via visa/debit then monthly payment unless you wanna pay a lump and then hope for a lump back
i think youd lose a bit of your deposit and admin costs even if you were to cancel after a day... are u insured to drive another car 3rd party on your existing insureance?? most fully comp policys and some tpf+t ones cover the policy holder to drive another car third party only, if you are just drive it.. if you get stopped etc pretend its a girlfriends/mates new car and your driving it home for em... would save messin about.. i know its not 100% legal before people start but for an on paper move its nearly bullet proof