Property that is above the Market Valuation

Here's a real experience of making an offer for a property where we had very little bargaining power.
The prices quoted here are all for illustration only:

Commercial Properties

There was an advertisement for a commercial property, with very few transactions in that area.  The asking price was RM590k, but bank valuation was only RM450k, on top of that, the rental yield was about 4.9% only.  However there was potential for further capital appreciation, seeing that there are new development in that area. Based on that, we tried to make an offer for 450k, with the option of going up to 500k.  However, the agent told us that we have very little bargaining power, the seller was really "not desperate" and would sell to whomever offers the highest price. 450k was impossible, not even 500k, because the owner already got offered >500k.
So we decided to back out.  Low rental yield and low bank valuation means that we have to come out with substantial cash.
2 weeks later, I called the agent just to check if the property was sold, and it was.  The actual transacted price?  >RM 600k, higher than what the agent had advertised.  No doubt there was potential for capital appreciation, but is it worth to pay a premium price now itself, before the actual valuation, and the rental just equal the loan instalment? What do you think?