Modern method of auction sales rose almost 15% year-on-year and now account for a disproportionate share of complaints to The Property Ombudsman, prompting calls from conveyancers and traditional auctioneers for mandatory disclosure of the fees estate agents earn when they recommend the route. The May 2026 TPO report found property auctions represent just 2% of home sales but generated more than four times their proportional share of complaints, with MMoA representing "a recurring issue".
The commercial tension is stark. Alto promises agents "at least £2,500 for every completed auction sale, on top of their standard vendor fee". iamproperty reports £45.6 million paid in fees to agents from 12,065 properties sold—an average of £3,779 per sale. That compares favourably to typical private treaty commission on a stalled property that has already been reduced. The agent who failed to sell a property at asking price can earn materially more by recommending MMoA, creating what Daniel Marsden of Probate Auction calls "a potential conflict of interest worthy of scrutiny".
Buyers pay substantial, non-refundable reservation fees before their conveyancer has reviewed the legal pack or identified title defects, then face a 56-day completion deadline. Conveyancers inherit the liability: advise the client to proceed with a defective title and risk negligence; advise them to withdraw and they forfeit thousands.
The complaint pattern
The Property Ombudsman identified confusion around reservation fees as the primary source of MMoA complaints. Buyers believed the fee would be applied towards the purchase price, would be refundable if the transaction failed, or would not be forfeited where the seller caused the failure. TPO's casework found that "even where reservation agreements are clear, complaints may still arise if the surrounding communication is not".
Chief property ombudsman Lesley Horton said: "The point of financial or legal commitment must be made impossible not to miss." The report warned that buyers approach MMoA transactions with expectations shaped by the private treaty market, particularly where the process is marketed in accessible or familiar terms, leading to misunderstanding about timelines, commitment, fees and the extent to which the transaction remains conditional.
The ombudsman also noted that sellers can experience poor outcomes where the auction route is recommended without sufficient advice, particularly where they are not properly advised on the differences between auction and private treaty, the trade-off between speed and sale price is not discussed, or businesses do not take adequate steps to understand the seller's objectives before instruction.
The conveyancer exposure
Rob Hailstone, founder of Bold Legal Group, said the MMoA structure places enormous pressure on conveyancers. "A conveyancer must not allow a deadline to cause them to recommend that a client accepts a title defect, lender issue or other legal problem simply because the alternative is losing a substantial reservation fee. The correct legal advice must remain: is this property safe for the client to buy?"
In a July column for Today's Conveyancer, the anonymous Secret High Street Conveyancer described clients who almost lost a £5,000 reservation fee on a property with an unmortgageable title and missing leasehold documents. The clients had been told by their estate agent that MMoA was "a common arrangement" that made the process quicker, "without knowing what this entailed".
Hailstone listed the scenarios in which a buyer can do everything reasonably expected and still encounter problems: the mortgage lender takes longer than anticipated, the title contains an unexpected problem, a lease is defective, a required document cannot be found, a management company fails to provide information, an issue arises from a search, or the property is not acceptable to the buyer's lender. "These are not necessarily failures by the buyer. Yet the buyer is the person who may have put thousands of pounds at risk."
One conveyancer commenting on the column said they would not act for buyers on MMoA transactions again "until there is proper regulation in place". The professional indemnity exposure is clear: conveyancers must complete due diligence within 56 days while a client faces forfeiting thousands if the transaction does not proceed, creating pressure to overlook defects or incomplete information.
The agent incentive problem
Marsden argues the method "rides on the coat tails of traditional auction" by borrowing terminology—auction, bidding, countdown, commitment, speed, certainty—without delivering the legal certainty of exchange on fall of the hammer. "When the bidding finishes you don't have the thing that has always given traditional auction its certainty: an exchanged contract."
He said agents are "openly marketed higher fees by the platform providers, faster payments and additional revenue streams for moving properties into these models, including properties that have already been reduced, stalled or fallen through". He called the arrangement disgraceful: "They've somehow created a system in which failing to sell a vendor's property through private treaty can create an opportunity for the same agent to earn considerably more money from the next method they recommend."
In August 2026, Alto launched its MMoA offering with marketing that made the agent fee the lead benefit. "Every agency has stock that's quietly going nowhere. The property that's had two reductions and a buyer walk away", director of partnerships Stuart Pick said in the press release. Alto claims fall-throughs run at under 1%, "because the buyer pays a non-refundable fee and is committed from the moment the auction closes". That claim does not clarify whether transactions that extend beyond 56 days are counted as fall-throughs, or whether buyers who choose to forfeit reservation fees rather than complete are included.
Marsden said vendors are entitled to know whether the recommendation they receive is about the best way to sell their home or about branch revenue. "The driver here seems to be fees. Are you referring me to this method because it's better for me and delivers a better outcome? Or are you suggesting it because you earn more money for the branch? That's the question all agents should be able to answer with a straight face."