Hello
If you want someone to build your website, I would reccomend going local. I have had a website for several years and have had work done via finding people online to do the work. When I did a full re-design I decided to stay local and it was the best move I ever made. I could go to their office any time and during the design process we could make changes in real time.
I build my first three websites and other than the learning curve, the only real "con" is time. it is alot more time consuming than people think.
As far as features go, you want a place to sign up for email newsletter and whatever social media you happen to be using.
you want to bring people to your site so you want to offer "Free" stuff. Recipes, games, coupons, etc.
As far as costs go, you should have a reliable host and that should cost around $10.00 - $15.00 per month. By going local you can have them teach you how to add things to the site so maintenece should be on a as needed basis. My website is pretty maintenence free right now,
Do not worry weather they have done restaurant websites or not, it really does not matter. Most design companies use standard templates and adjust them to the clients needs. My website sells golg clubs and none of the people who worked on it play golf, but it is a great site none the less.
You can take a look at it here
www.crosshairgolf.com we are making updates right now so some of the links might not work, but you will get the idea.
Al