Verizon will pay $4.8 billion for the yahoo parts of yahoo. If you also include the $40 billon of Alibaba the total number is about the same (but Microsoft still dodged a bullet)
Money is pretty much free in an environment where interest rates are nearly zero. This is true whether you use debt or equity to finance a venture. If my risk-free rate is nearly zero, then I'd be willing to loan you money, or invest my money in your venture, for a fairly slim expected return.