This what I'm doing. My sales price is $86k including sales tax. I'm coming to the table with $40k of my own cash and $15K from a home equity line of credit for a total of $55k down payment leaving $31k to finance. My cash outlay will be about $700 for 4-5 months until tax time. $400 with Alliant at 1.49%, approx. $300 on the line of credit. I opted for a delayed deliver in the Sep- Oct time frame to lessen by burden for as short a period as possible. I'm expecting a $16k tax refund in Feb 2017 which will be used to pay off the line of credit bring my monthly cash outlay down to $400 a month.
Most lenders have criteria for what's a new car e.g. Age, mileage etc. and what's considered used with higher rates for used. Refi's cost more. Most would not allow me to apply my refund to the original loan and refi under one roof without penalties (higher interest rates). Prior to today I was thinking of using two lenders not including my line of credit, but this was a little problematic trying to go with the highest rate for original loan (short term) and refinancing with the lower rate lender for the long term.
I don't work on Wall Street or wear pinstripes on a daily basis, just an old country boy trying to save a buck thru CREATIVE FINANCING
Hopes this helps!