my concept is simple, though there are more factors to consider.

if you can borrow money to pay off some loans, then you have to compare cost of borrowing. borrow from a lender with lower rate to pay off lender with higher rate.

you'll have to convert your car loan to an annualized rate instead of the flat rate, then do a comparison. usually car loan has a higher annual rate.

another factor you may have to consider is liquidity. since you're doing renovation, you might want to keep cash in hand. for me, i keep my cash in a current account that will reduce principal of my home loan. so i keep my borrowing cost low but still maintain a level of liquidity incase i need to spend on anything. my home loan allows for this.