I used to be an EA, and I see merit on both the op's and tlh's arguments.
The EA is working for the vendor, and the property ought to be marketed til exchange, but with the honest proviso to any potential viewers that there is a sale arranged. Lets face it, if someone who has no chain, offers £5k more than you, and you are reliant on 5 people below you, then to keep selling to you would be a no brainer.
But again, there is a *huge* conflict of interest in the estate agent managing "your" purchase. If theres a difficulty, and the same solicitors are working for the seller, would you get the best advice? And why should the agent prefer you, with 5 properties in the chain below, using their mortgage service over the aformentioned no chain cashbuyer? That would be massively unethical too.
I suggest you ask for the managers name, discuss whats been said, and say you will be reporting them to the Estate Agents Ombudsman for a complaint. I would also tellthe seller how his house is being marketed unethically.
Regrettably, certain "chains" of agents are like the Halfords of bike sales, you just don't know who they are.
*cough* countrywide is a word that should ring alarm bells. But they are not the only ones.
I actually pretty much refused to get involved, past letting a FA vet the purchaser over the phone, just so I could be assured the buyer was good for it. I was also scrupulous about "chain checking" and used to roast other agents it seemed every day, for not knowing what the chains were doing....
But then I was one of the few, genuinely honest ones. And I have verifiable proof, having sold building plots or dilapidated properties to private purchasers for 2x what a builder would have paid, and lost out on "resale" commissions and "relationship building" with developers. I saw a place in the last recession, I valued it at £100k, every other agent in the village valued it at half that, and we got £105 in the end. A lot of delelopers had wanted that plot, and no agent would value it honestly.
Having said that, if I had sold several 2 beds at 55-58k, (when stamp duty was 60k), and I saw a indentikit 2b estate house, I;d tell people to within £500 what it was worth, adding for double glazing, a decent view, a nice kitchem/bathroom. But I never "over valued" ie telling that person Yeah, we'll get you £65k, wioth a view to getting a board up, a pic in the window, and 16 weeks to work on getting the price down. Thats what target driven big name estate agents do. If it was worth £57, I'd say it how it was, but most people dont appreciate honesty, think your a fool, that their house is "always"worth more.
Frankly, in England, people get the agents they deserve, which are a piss poor bunch of chancers.