How HDB resale transaction work?

[mobiletaurus]

Hi,

I intend to buy a HDB resale unit due to recent changes of procedures of valuation process, now a bit confused.

As I read through some property-related websites, it was said that buyer and seller must agree upon the selling price. Only after then, the buyer can get the valuation report.

Scenario 1:
Agreed selling price:$380k
House valuation: $400k
Does it mean that I just need to pay $380k and the seller "rugi" 20k?
Loan amount only based on house valuation of $400k?

Scenario 2:
Agreed selling price:$420k
House valuation: $400k
Does it mean that I need to pay $420k?
Loan amount only based on house valuation of $400k?

If I as a buyer already got the HLE from HDB of $380k and CFP in OA of $45k.

Then what should I take note?

Thanks.