A friend of mine who plays sax/piano/keyboards did this for a number of years ...he would play kb for the ceremony, piano and mix in sax with backing tracks for the cocktail hour, and add that to DJing for the reception ... it helped that his son-in-law also did DJ and radio work and kept him up-to-date... it worked well for him until he got tired of hauling all that 'stuff' around ... now he does mostly ceremoies and/or cocktail hours on piano or kb ...
t.
_________________________
t. cool