No relative involved... Involved a CB Kia whom I used to regard as a long time buddy... CB Kia took a renovation loan and asked my help to become his guarantor... CB Kia defaulted on his payments and kept quiet about it until I received the Letter of Demand only few weeks ago...managed to find him and he told me he running into financial problems and all the sad stories came out... Some of which were true like his dad now presently suffering from 4th stage cancer....
Neither be lender nor guarantor to be.
Especially for car or renovation loans guarantor for these are discretionary spending. Something we can do without if one does not have the money.
Take it as lesson learnt and move on.
I am sure your credit score won't be affected if the bank is able to allow you to pay by installment.
Luckily it's only 20k, can't imagine if it's 100k. Then really big problem for you.