With difficulty I imagine, given that I imagine you have a poor credit rating. If you are in an IVA then you will need permission, I believe, to enter into such an arrangement.
I am in an IVA and have a PCP type plan with a balloon payment at the end.
Car HP might be tricky - but I do know of a company that can do car leasing. Happy to pass their details on if you want to make contact with my via my website.