Absolutely, you should wait until you get here. There is so much accommodation that is not advertised eg we found our place which is a perfect family house for us from a sign nailed to a tree.
And I'd be very very wary of renting something (and probably paying a years rent up front) sight unseen. Who knows, there might be a five story hotel being built right next door!
So rent something short term (maybe give yourself a month) Bali Advertiser is a good place to start and then, literally, get on a bike and have a look around.
It took us 2 weeks of hard work to find the right villa (and you are looking for a villa not a house) fo us. So many of the villas out there are so not suitable for families with younger kids.
hope this helps
Phil