Cofounder Agreements

[The Giant]

For two years now, I have been part-timely working with some travel agents online on marketing and strategy. Then,I came with an idea of having travel portal for tours and activities. I hosted site (not live now) and written business plan. Meanwhile, I still work with agents, I met with one lady (lives in London) who was my prospective client. I introduced her my idea she said she was interested, but she wants a plan and I gave her, then I said we need some funds to get us started. She said, she can contribute at the moment only 13% of the fund required in return for equity. She wants protection from her funds(but I have no security) and she want everything to be formalized including agreements. Please I need your help on this, your advice, any cofounder agreements?
Thanks...