Also be careful not to charge too low or you'll be an ourtsourcee; which means your services are worth more than what you're charging (most of the time). Hence this: My statement isn't always true but 9/10 times it's true in the web designing. I think the only main case when taking outsource work is okay is when you know the person contracting you is doing a big job (IE: redesigning & coding Adobe's website), it would make sense for the general contractor to hire subcontractors. Just watch out for normal people trying to sub your work in, usually it isn't worth it or you can get better.
For clients in the real world, price is not too much of an issue for site design...they're much moreso concerned with quality and appearance.
It is depend to how good are you. If you can provide a first class design, then you might get more then that