How long should i book my dj for ? Help!!

Daughter's DJ provided the pre-ceremony music as guests were seated, processional & recessional music, mics for the ceremony (officiant and on the groom's lapel for the vows), music for cocktail hour, and then music & MC for the entire reception. Ceremony began at 3:30 and reception ended at 10, so we booked him for 7 hours, 3-10pm. Outside of those hours was his time for setting up and packing up his equipment. I think we paid $1300 (plus a voluntary $100 tip), in So Cal. (He was awesome from the minute daughter first talked with him on the phone through the very last second of the reception, and well worth his charges.)

We had our DJ the entire time. He provided microphones & music for the ceremony, music for 20 minutes prior to the ceremony when guests were arriving, cocktail hour music, reception music, microphones for speeches, and he was an emcee for the evening. So 6 hours total not including set up & take down.

I am a bride-to-be who is also a wedding vendor. Here are some things to consider:

1) If he comes for the reception only, he still has to get there before everyone else does in order to set up without interfering with your guests. Does the 4 hours start when he starts performing/doing DJ things? Or when he arrives to set up? (see question 1 below) That will help determine how long, total, you will need him. If he has to get there at 4:30 to set up for your 5:30 pm ceremony and your timer starts when he gets there, then you will need him for 6 hours total. If he counts DJ time only, then you're paying for 5.5 hours (5:00 pm - 10:30 pm) because most DJs will put on music as your guests arrive (typically 15-30 minutes prior to your ceremony start time).

2) You will want sound support for your ceremony - someone to play the music while guests are being seated and for your processional and recessional. Also, a mic is usually needed in about every situation to hear the officiant and your vows.

Here are some questions to ask your DJ:

1) Does the total time of 4 hours include set up and tear down time? If so, when does the timer start on the 4 hours? When he gets there or when he starts DJing?

2) If he were to set up sound for the wedding ceremony, what is the extra cost? (there SHOULD be a charge for this if he has to bring separate equipment)

Hope this helps!
-Christine