I am buying a firm with an expected perpetual cash flow of $1,000 but am unsure of

Question:

I am buying a firm with an expected perpetual cash flow of $1,000 but am unsure of its risk. If I think the beta of the firm is .5, when in fact the beta is really 1, how much more will I offer for the firm than it is truly worth?
Assume that the risk-free rate of interest is 6% and the expected rate of return on the market is 16%.