It's always important to ask them for a website that they like and this gives you a target. When you meet and beat that "ideal" website - they're often incredibly grateful. I never attempt to retire off my prospects :)
I've done bakery and pastry shops and in addition to my project bid, I negotiate permanent discounts and even a few let me eat for free whenever I'm there.
I've done furniture stores and in addition, I get permanent employee discount.
I've pitched housing developments and in addition, I'll get employee rate for rent.
Lawyers are the same - you can rely on them to help look over your contracts. They're just as important, so I often do exchange in hours.
Just be a nice developer and realistic. We're blessed to know what many people don't and a few bad apples like to take advantage of their clients because of this. Be a breath of fresh air and watch the doors open.