Planning a trip to La Paz

Hi,

I'm planning a trip to La Paz for an IT and Telecommunications convention.
I need to present a budget to my company before the trip gets approved.

I would like to know how much should I expect to spend in cabs and what is an average price for having breakfast, lunch and dinner.

If I have some free time, what places should I check in La Paz?

Any advice you can give to some one that never has been to Bolivia is welcomed.

Thank you.

Pablo