Avoid shopping on weekends or in the evening. These are heavy traffic times. There's already a lot of sales activity going on and dealers may not be as motivated to meet your price. If it was built more than 4 months ago, it's a slow mover and you should be able to negotiate a better price for it. Hot, in-demand models are sold closer to full price.
Dealers are willing to reduce the price more for slow movers.
You can sometimes get a better price if you order the model with just the options you want from the factory. You can easily call the lender for this information. You may also be able to get a lower interest rate on your loan if you shop ahead. You don't want to be stuck with a vehicle you can't pay for. And remember that the longer the term, the greater the cost of the loan.