This is only here so others don't needlessly repeat our experience. Neither my sister nor I (nor our spouses) had any experience of selling a house, so when my Mum died, selling a house was a new experience. Generally, it was much as expected - but not quite.
Many people call themselves professionals. I'm no longer naive enough to think all mean the same thing when they use that phrase. In essence, it usually really means that's how they earn their money. That is quite different from my own experience as being a "professional" accountant, where the rules are quite clear - basically, our client's welfare must come above our own financial interests. We are even required to have indemnity insurance in case we inadvertently do something that costs our clients money, although with the training we go through, this doesn't happen often.
When we agreed on the sale of Mum's house, we thought that was the end of the matter. The settlement date coincided with an outing with our son. It was a great day - until our lawyer rang my cellphone. The building inspection had revealed some issues that meant they wanted to lower the price.
Given that my sister was unavailable to discuss things during working hours, I was in a quandary. We resolved the issue, but what had previously been a fair and reasonable experience left a bitter feeling behind.
I now know that this is regarded as "normal" these days. I understand that a builder's report can reveal items that need to be resolved. It's in the contract, and I have no problem with that. But we had signed the deal some time before the settlement date, and yet nothing had been communicated to us prior to the settlement date.
The only reason I can see for leaving it till the last minute is to add pressure - hardly a professional attitude. If I were to repeat the process, I would want to add a provision that any request to vary the price must be received, say, 48 hours before settlement time. That way, all vendor parties can discuss it and respond accordingly.
I suspect real estate agents might not be keen on this - but if so, that raises a question as to their real level of professionalism.