We cleaned a two storey home yesterday with high louvres in the entrance void. The windows were covered in mould, cobwebs and caked on dirt — because they hadn't been properly cleaned since the house was built. The cost to clean inside and out: $1,450. The same house with large fixed panels instead of louvres? Around $800. That $650 difference happens every single clean, for the life of the house. Here's what nobody tells you before you build...