The people you want to spend time with, often won't be the same as those who want to spend time with you.
You and your fiancé will naturally want to spend time discussing things with your families and friends. But the professionals and salesmen might be more eager than your families and friends, to spend time with you.
Decide what proportion of time you will spend with each person, and stick with it.
The primary concern of wedding professionals is either to make financial profit, or to make the day perfect for you.
It's difficult to discern between these two types since the profiteers are expert at camouflaging their ultimate motives. That's life of course, and you will meet similar people when you buy a house or any other significant purchase. Weddings are no different and once you accept that, it is much easier to be careful and not to waste money on something you do not want. Pause and ask yourself: Is it in my interests to do this? If so, do I need to do it now or am I better off leaving it to another time? When you have made a conscious decision, communicate it and act accordingly.
On the other hand, despite these negative warnings of the pros, remember that you will be working with people who have been involved with countless weddings.
They will be working on your wedding as a business project. If you also treat the planning as a business task then things should go smoothly. Take advantage of their experience, but remember that this is YOUR wedding. The pros are there to make money so don't let anybody take advantage of you.
MC? DJ? Singer? Band? Conjuror? Whoever you choose, make sure the style of these people is YOUR style. If not, you are wasting your money.