[biot]

  > How much has doing the startup cost you. If you're
  > bootstrapped you've probably both put personal funds in as
  > well as a salary opportunity costs. Thats your base.

This is irrelevant. If you've blown $50M of your personal funds on a startup with nothing to show for it why would it be up to the acquiring company to have $50M as the floor price so that your losses are covered? If you bought a used car, would the base price incude the cost of gas that the seller spent?

It boils down to some combination of three things: people acquisition costs, domain expertise value, and technology worth. There's a fourth factor of inherent value of the business itself (outside of technology and people), but the OP stated they have neither revenue nor customers so that's likely a zero. All these are values that the acquiring company can put a number on. Price accordingly.