Do your homework and put it down in black and white. I put my stuff in the "cart" then print it out. I go to the other vendors and do he same. You'd be surprised. Just a week ago I was going to order from a preferred vendor for years. Well, turns out they were over $15 higher on the exact same parts and that was after a discount.
.... do the math. Cheap is cheap no matter which vendor it comes from so why pay more for cheap stuff when you can get the same cheap stuff cheaper somewhere else.