Agreed, but same mindset also applied to bank loan, they stretched to 33% of income... some even stretched to 40% from bank. I found that 2 major reasons they will do this:
1) Money values keep depreciate (inflation, weak buying power in future for same money value)
2) They think their income will keep increase thru annual increment/other sources/etc.

P/S: Zero downpayment programme, it also happened to some housing development project (just need booking fee, free S & P and downpayment) ^^
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