Best bargaining chips at dealerships?

Hi all,

Family is growing and as such, I am in the process of upgrading to a medium SUV. Mainly looking at the Subaru Crosstrek and Mazda CX5 right now (but open to similar alternatives). Open to new, demo or (slightly) used cars.

My main concern is: I absolutely HATE AND SEETHE when I'm taken for a ride by salespeople. I have done a fair bit of homework and will continue to do so in the leadup to purchasing a car.

I was wondering if anyone has any good tips when dealing with the inevitable bullshit at a dealer and hopefully get the price down as much as possible. Also, anything to look out for? I know finance is generally a scam. Would it be best to secure a car loam from a bank prior?

Cheers!