[nicsantana]

I have to agree with amitagarwalx. You should revisit your statement of work. I've been doing some work at Ad Agencies and this happens all the time especially now with Brands wanting agencies to build sites, ecommerce, etc.

I remember one time we agreed to do a project for peanuts so we could use project as a case study. It was a creative fit for us. Shortly after the client wanted three additional features that were not agreed upon, I quickly had the conversation with them and told them this was outside of the scope and it was going to be additional and gave them the costs. They ended up going with only one (1) of the three features and agreed to pay the additional fee.

My point is if you're trying to build body of work agree to parameters you're comfortable with. If you feel like you're being taken advantage of then walk away. You can turn work away. It's best to be upfront, you want to build a good working relationship with everyone but not EVERYONE is going to be good client. It's important to manage their expectations.

If your client is unaware of front-end technologies then make him/her aware of the process. In fact have them prototype it first so you have fewer changes later on.