I know how it is. You are on an extremely tight budget, you need to find a florist or caterer or baker or photographer to make your special day happen. Well, you have a friend, who knows a friend who knows someone else that can do the job....AND they are supposedly great!
That's awesome, but guess what? It is still your big day, no matter the discounted price you are getting. So please, be sure to always have a meeting with your vendors, explain your desires for your day, have them draft a contract with your agreements, sign, send them a copy and file away!