Just back last week, we found that a night out for tea for a family of 4 with a teenage son 15 and daughter 13 was usually arround A$50.00 this included a couple of drinks, Entre and Mains - it was not often we could fit in Desert. Often we ate out for only $7.00 a head. This was at normal restauraunts not cheap stalls.
We ate mainly around the Legian area - Lanai,Restarunte Italiano (part of the Kumala Pantai), Uncle Norms, Legends etc
Hope this helps some with their budgeting
Fernandez