Even venture capitalists rarely venture outside the particular range of target companies in which they invest. They follow strict guidelines, some of which are established when the partnerships are formed. Investment money is very expensive at this stage because the risks are high when all you have is an idea. The founders should do everything possible to fund the startup stage themselves. You'd be amazed how far you can stretch a dollar when you're strapped for cash.
People are usually happy to help.
You can base the price of the stock on fair market value determined by what outside investors are willing to pay. To determine the value of sweat equity, subtract what you get paid during startup from what you could have made on the open market. You may also consider accepting investments from friends and relatives at this stage. Conventional wisdom says that's a bad idea because you stand to lose a friend if your business fails. But if you present your opportunity objectively, state the risks clearly up front, and remain open and honest throughout, your relationship will probably endure, and it may even be strengthened.