An earn-out is won or lost in the twelve to twenty-four months after completion, not in the negotiation room. The seller who secures their full deferred consideration is typically the one who understood exactly what they were measuring against, actively protected landlord relationships during the transition, and challenged calculation errors in writing as they arose — not retrospectively.
This guide covers the practical steps a letting agency seller can take post-completion to maximise their earn-out outcome. For the contractual structure of earn-outs and how AMFI is defined, see The Estate and Letting Agency Earn-Out. For the broader transaction process, see how to sell your estate or letting agency.
Know the Earn-Out Schedule Before Completion
You cannot maximise an earn-out you do not understand. Before completion, read the earn-out schedule in the SPA in detail — or have your solicitor walk you through it until you can answer the following questions without hesitation.
What is the AMFI definition? Which fees are included — management fees, renewal fees, check-in and check-out fees — and which are excluded? How is the baseline AMFI calculated: as a run-rate at a point in time or as trailing twelve-month income?
What is the measurement period? When does the earn-out period start — typically the completion date — and when does it end? Are there interim measurement dates with tranched payments, or a single measurement at the end?
What is the target, and what does it reward? Some earn-outs reward pure retention: if AMFI holds at or above the completion baseline, the full deferred consideration is paid. Others reward growth: the earn-out scales upwards if AMFI exceeds the baseline. A growth target changes your incentives during the earn-out period — you have a direct financial interest in new landlord instructions, not just in protecting existing ones.
Is there a collar? A collar is a floor below which the earn-out pays nothing. If the SPA includes a cliff at, say, 85% of baseline AMFI, a 14% portfolio decline costs you the entire deferred consideration — not just the portion attributable to the shortfall. Know whether you are in a proportional structure or a cliff structure. In a cliff structure, every at-risk landlord carries a disproportionate financial consequence.
Protect Landlord Relationships During the Transition
The single most effective action a seller can take to protect an earn-out is a structured programme of personal introductions from the outgoing owner to key landlords — made before and immediately after completion.
Landlords leave when the relationship changes and no one has prepared them for it. A landlord who has dealt with the same person for eight years and discovers the business has been sold by seeing a new name on their management statement has already started evaluating alternatives. A landlord who has been personally introduced to the new team by the person they trust — told directly that the business is in good hands and why the sale was the right decision — is far less likely to make an enquiry elsewhere.
Identify at-risk landlords before completion. Before the sale completes, produce a tiered list of landlords by attrition risk. Prioritise:
- Landlords with a documented complaint or active dissatisfaction
- Landlords holding their properties under a short-notice management agreement
- Landlords with a direct personal relationship to the selling owner rather than to the management team
For each high-risk landlord, plan a personal contact — a phone call or meeting involving the seller directly — before the earn-out period starts. This is the single highest-return investment of time in any earn-out.
Frame the transition positively and specifically. Do not offer a generic reassurance that “nothing will change”. That framing is unconvincing and creates a hostage to fortune — something will change. Frame the transition in terms of what continues or improves: the management team the landlord knows is staying, the buyer brings additional resource, the landlord is important and will continue to be looked after personally. Be specific.
Support the New Management Team
Non-interference covenants prohibit sellers from actively undermining the buyer. But many sellers interpret non-interference as a licence to disengage entirely. That is a misreading of their obligation and, in earn-out terms, a costly one.
Active support is permitted — and in your direct financial interest. Make yourself available for questions from the new management team in the months immediately post-completion. You carry institutional knowledge about individual landlord relationships, historical arrangements, and portfolio context that is not in the data room.
Attend key client meetings where your presence provides continuity. A landlord review meeting in the first three months after completion where the previous owner appears alongside the new team signals stability and personally authorises the transition in a way that no letter can replicate.
Facilitate the handover of relationships, do not gate-keep them. Introduce the new team to landlords as your successors, not as a temporary arrangement. A seller who manages landlord relationships down during the earn-out period — rather than actively transferring them — is creating the attrition their earn-out cannot afford. Non-interference means not competing; it does not mean not helping.
Monitor AMFI Monthly
Request — and insist on receiving — monthly AMFI reports from the buyer throughout the earn-out period. Do not wait for the end-of-period accounts. Track each month against the completion AMFI baseline. A monthly tracking schedule should show:
- Properties under management at month end
- Management fees invoiced in the month
- Properties lost, with the stated reason for each departure
- New properties added
- Running AMFI position against the earn-out target
Identify a declining trend early. A loss of two or three properties per month is invisible in a single snapshot but materially significant over a twelve-month earn-out. If the trend is downward, discuss it with the buyer proactively — before the measurement date, not after. A conversation at month four about a managed portfolio decline is a very different negotiation from a dispute at month twelve about a final calculation.
Challenge Incorrect AMFI Deductions
The earn-out accounts are prepared by the buyer. Errors — whether innocent or otherwise — should be challenged in writing at the time the deduction appears, not retrospectively at the final measurement date.
Buyer overhead allocations. If the buyer has allocated central overhead costs to the earn-out entity — group management charges, central finance or HR costs, IT infrastructure fees from a holding company — those allocations may reduce reported AMFI or business income. Challenge them in writing at the point of discovery. Overhead allocations from the buyer’s group structure should not reduce the earn-out AMFI calculation unless the SPA specifically and unambiguously provides for it.
Gap property exclusions. Properties that were temporarily between tenancies at certain points in the measurement period should be treated in accordance with the earn-out schedule in the SPA. If the SPA provides that gap properties are included at their expected management fee rate, a buyer who excludes them is understating AMFI. Check the schedule.
Merged portfolio income. If the buyer has acquired additional letting agency portfolios during the earn-out period, management fee income from those separately acquired portfolios must be excluded from the earn-out AMFI calculation. The earn-out measures the retained performance of the business you sold — not the combined performance of a larger entity the buyer has assembled since completion.
Raise any disputed deduction in writing at the time it arises. A contemporaneous written challenge is significantly stronger evidence than a complaint first raised at the end of the earn-out period.
Comply With Your Non-Interference Obligations
Compliance is not just a legal obligation — it protects your earn-out rights. A seller who breaches non-interference covenants gives the buyer grounds to argue that any AMFI shortfall was caused or contributed to by seller conduct. Even if the breach was minor and technically unrelated to the shortfall, it weakens your position in a dispute.
Non-interference covenants typically prohibit soliciting the portfolio’s landlords, recruiting the transferred staff, and setting up a competing business within a defined radius and period. Know exactly what yours prohibit. If you are uncertain whether a planned activity falls within the scope of the covenant, ask your solicitor before you act.
Know and Use the Dispute Resolution Window
The earn-out schedule in the SPA will contain a challenge window — typically 20 to 30 business days from receipt of the final earn-out accounts — within which you must formally notify the buyer of any dispute. If you do not challenge within this window, the earn-out accounts are treated as final and agreed.
Know this date. Put it in your calendar on the day you sign. The calculation of when the window opens depends on how “receipt” is defined in the SPA — check it before completion.
The dispute resolution procedure will typically require the parties to attempt to resolve disputes within a further defined period, with referral to an independent expert accountant if no resolution is reached. This mechanism is faster and considerably cheaper than litigation and is specifically designed for earn-out disagreements. Use it. Do not treat litigation as the only alternative to accepting a figure you dispute.
Plan Before Completion, Not After
The earn-out period begins the moment contracts exchange. Preparation — understanding the schedule, identifying at-risk landlords, and setting up monthly AMFI monitoring — is significantly more effective when done before completion than reactively once the period is running.
To understand how earn-outs are structured at offer stage, see our guide to understanding an estate agency offer.
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The Business Acquisitions Group — specialist brokers for estate agency and letting agency sales across the UK.