I’d like to avoid haggling and it’s worth it to me to pay a little more. I was thinking that if a dealer sells cars with a “no haggle” policy that would apply to their leasing as well, is that true?
From what I understand, the 2 things you can “haggle” for in leasing is the (1) actual sale price and (2) the MF markup by the dealer. Almost everything else is published and pretty set
You’ll probably want a lease broker.
Think of haggling as a conversation. People do not haggle because they are poor or cheap. Quite the contrary, the biggest negotiators are the wealthy ones 
Information is key, Before going to dealer, find out the sales price from car services like truecar or ads from competitive dealers.
Dealer says, we would like to sell car for A. You say, my budget is around B and I see some prices around that number. Dealer counters with A*. Then you come up to B*. Repeat a few times. Then hopefully you both agree on C which is between A and B. Repeat a few times and it’s more like a dance or conversation. No need for high stress. I agree that the finance managers certainly bring on the pressure tactics but a simple and polite no to the add-ons does suffice.