I list most of my items with a price and best offer.

This allows you can sell the item quicker, withoug waiting for Auction end.

If a price is  offered, I still have control whether to accept or not.

However, there are some items which I put a fixed price.

I have just learned this through experience.

Finally, it is at times frustrating as a buyer,  to have to wait for the end of auction,

as you may want the item,  but are not able to bid at that particular time.