Tim any of the common songs will work , before the service when people are being seated, love songs will work, I would use songs that the average person in attendence would recognize...Wind beneath my wings,Through the eyes of love,Wedding song, etc.. Specialty songs , Cannon in D, Bridal Chorus, Wedding march,,Lady is a tramp[just kidding about the last one].. As for fees, are they friends and would you be attending any way? If so, with out future consequences, I have performed in this situation with out a charge, [a wedding gift] They will remember your contribution forever..If a charge is neccessary, I think $250 is about average for a basic service..Make sure you know the procedure and order of the advent..If possible have someone within the organization of the wedding, cueing you..Have fun, it is easy and should be enjoyable..You are in a win/win situation..