Will this person be an active "partner" in the business or is he just investing?
Do you share the same vision & purpose for the company?
Do you have the same core vales?
Why do you think this capital will make an big difference in the results? (if the economy is the issue - more capital won`t change that)
If you decide that this person would be an asset to the business - then you need to define the terms of the exchange.