Everything is negotiable in the purchase transaction. When I represent the buyer I write it in the contract that the seller pay for all the HOA and transfer fees, when I represent the seller I counter so that the buyer pays for it.
If your agent did not defend you on that issue it looks like you are stuck, I recommend you read the fully executed purchase agreement and everything that you have signed to make sure what you have to do/contribute to the transaction. Based on what you say, looks like you are stuck with $599. Is $599 worth jeopardizing the escrow? That is up to you, did you really like the offer?
I really take pride in negotiating everything on behalf of my clients, explain every line we are signing.
Some agents do Real Estate as a part-time job, some agents don't understand contracts, some are just eager to get into escrow and collect their commission, and there are some agents like me that are very detail oriented that always defend their clients best interests. There is a pie chart to be made for sure and I can't tell you how the percentages would be, but I hope it helps.
The way I look at it, I want for my clients to be my best referral source, I feel that if a client does not refer me 3 transactions I did not earn their business, would you reward your existing Realtor with more business? I constantly ask myself if I am earning repeat business from my clients and the results speak for themselves, to this day, I have not spent a dime this century in advertising myself on newspapers, internet, magazines, etc. because my clients do the marketing for myself. I hope this helps, I hope you got a very good deal for yourself as the market has turned in favor of the sellers.
BTW, that is a very good question.
Hector R. Gastelum
Realty Executives Dillon