Why would the agent get a higher price?
* Is it because, as per the example above, they have made up a higher offer which caused the genuine bidder to have to increase theirs? (which is completely immoral not sure about unlawful).
* Or is it because they can do a best and final process? Why can't an individual do that?
* Or is it because they can negotiate with a buyer? Why can't an individual do that?
* Or is it because they may be able to generate a larger pool of potential buyers? I agree this may be correct as its not possible for an individual to advertise on say Rightmove without going through an agent of some kind.
* Or do you think they have better vetting processes that is likely to mean the sale proceeds better? Maybe this is true.
I agree that the agent may have better solicitor links. But these days agents just make use of these large online conveyancing firms, which are pretty routine. You can still employ one of those firms as an individual.
And mortgage advice is often just as good (maybe better) from an online no fee firm (eg L&C) as the in house mortgage broker of the agent. When I bought my house I'd already started the process with L&C, but I was basically told by this agent that I'd not be seen as a good buyer if I didn't use their in house broker. Which is a complete lie but what could I do, I wanted the place. That cost me £600 more than it needed to.
The main value I see from an agent is the advertising coverage really, and maybe the arrangement of viewings, vettings and negotiation if you don't want to be involved yourself, but I disagree that an agent can automatically get a better price than an actively involved seller.
Good luck as an individual trying to get the best price via a best and final or negotiating stance. Agents will likely know the buyers well, have spoken to them, know how they've managed previous negotiations, know their max figures, know what they've offered elsewhere on other properties, know that they've pulled out on another deal and many other factors. There is simply no way a homeowner acting on their own will be able to get as high a sale price as an EA. That's even without considering, as you've said, the ability to create other offers and buyers and encourage price matching.
When I mentioned solicitor links I wasn't referring to them recommended a solicitor. An EA can phone up solicitors all the way along the chain, along with other EAs to find out what is going on, where a bottleneck is and assist with getting the chain completed and purchases done as quickly as possible (all in their own interest, they won't be paid until this happens). Good luck as a random owner trying to phone up the solicitors of a house or two up your chain, or even your buyers solicitors. They'll promptly tell you to jog on and they won't deal with you, where as they will to a certain extent with an EA who is acting on behalf of you for a sale.
One of my best friends in an EA, he takes properties on and often says about 30-50% don't ever make it to Rightmove. When he takes on a property he already has 5 parties he know will be interested in it, he already knows which one is a time-waster, which ones are ready to proceed, which ones can offer the asking price and which ones will bend easily when emotions come into play and they think they'll lose the property for the sake of another £15k.
You selling the house as a homeowner will receive an offer of asking and be delighted, the EA will know one party lost out of 2 houses last week and those offers were £20k above what the asking price the new vendor wants so he knows he can get another £20k for his client. Heck, even if he only gets £10k everyone is happy - the EA has a sale, the buyer is spending £10k less than they were last week for a property they want and the seller has just sold for £10k more than they expected.