Hi -- and IVA is as long as agreed at the outset -- usually 5 years ( often 6 if NRAM are a creditor, or the dividend is low) and these can both be extended by 12 months if you own your home and there is equity to release.
If you default on a loan which has a guarantor the lender will pursue the guarantor for repayment, regardless of the IVA. The lender will possibly tell them why.
My opinions are merely that .. opinions based on experience. Always seek professional advice.
IVA Completed 23rd July 2013 .... C.C. 10th January 2014