When purchasing a vehicle can you change to another vehicle if the papers have been signed but the financing not yet finalized?

absolutely but, beware..dealerships will try to get you to buy no matter what. even after the papers are finalized and you have even gevin them a down payment you can still either change cars or get out of the deal entirely. remember this, once that car is driven off the lot...then it is yours. they will say things to get you to buy it today and drive it home because they know that once you leave the lot its yours and if you try to trade it in it depeciates in value as soon as it leaves the lot. glad i could help.