How much would you charge for diverse graphic design related jobs for startup company?

So, you're estimating about 500 hours of work here, I'm going to assume on something like a freelance basis.  A good rule of thumb is that you can bill about 1000 hours per year when freelancing.  So, roughly, think about what a year of your time is worth and halve that.  Check out a salary guide if you honestly don't know what time goes for.  That's what your friend, if s/he is generous, will pay you for this. The problem you're going to run into with this is, though, you've done the work before setting an agreed amount.  This means you are, as we say in the business, shit out of luck.  Hours billed after the fact are generally worth $0.  More on this http://tinyurl.com/m9hcvg9. If you're going back to him to ask for money after the fact, you're putting you and him in seriously awkward territory.  Tread lightly. So, you probably have two options at this point: 1. Take a deep discount on your rate and cash out.  Be generous.  Your friend's http://en.wikipedia.org/wiki/Best_alternative_to_a_negotiated_agreement is to give you $0 and never speak to you again.  No bueno. 2. Negotiate something like an equity agreement with your friend.  He/she will appreciate noncash terms, probably.  You and your equity are probably going to be stuck to this friend and his/her company for the long haul, so negotiate some ongoing rate at this point as well so you have some money to live on.  If all goes well, Seqoia calls in six months and you're millionaires.

I hope you are learning from this experience. The first lesson I see is that you've entered into a working relationship without any clear guidelines for your fee for the work you're performing. This should always be spelled out at the beginning. I agree with Matt Ford about steps going forward, however, I'd add that you should take some training on basic business practices so you don't get exploited in the future. Clear communication with your client is extremely important in preventing misunderstandings, exploitation and disagreements. You're not a professional until you actually get paid for your work. Until then, you're a volunteer. Good luck!