The person who finds the property is not allowed to show the property to the potential purchaser. You must be either a licensed real estate agent or be working as a sales person for a licensed real estate agent before showing properties. If you breach these rules you may open yourself up to possible legal liability if you should happen to misrepresent the property and the purchaser takes legal action.
I believe a spotters fee for introducing the two parties would be the safest option, as you would only be setting them up for a meeting, without any involvement in the discussion or viewing property with them.