A couple signs a preliminary agreement for an apartment rated F on the energy performance certificate (DPE). Three months later, the energy audit reveals much more extensive work than expected, and financing wavers. This scenario is becoming increasingly common as regulations on energy performance tighten.
Buying or selling real estate in 2025-2026 is no longer just about finding the right price: it is necessary to integrate recent regulatory constraints that most traditional guides do not mention.
Mandatory energy audit: the trap that sellers and buyers underestimate
Since April 2023, an energy audit has been mandatory for the sale of homes rated F or G on the DPE. The requirement has since been extended to homes rated E. This document goes beyond a simple diagnosis: it details a costed work plan to achieve better performance, with two scenarios (step-by-step renovation or comprehensive renovation).
For the seller, not anticipating the audit extends the selling timeline by several weeks. The auditor must be certified, and slots are becoming scarce in certain high-demand areas. If the report reveals a significant amount of work needed, buyers negotiate the price down, sometimes significantly.
For the buyer, the audit serves as a concrete negotiation lever. One can rely on the estimated work costs to adjust their purchase offer. However, it is essential to verify that the auditor has indeed visited the property (and not just filled out the report remotely, a practice that exists). Feedback varies on the reliability of work estimates depending on the service providers.
Before trying to discover the Exact Immo site, which lists properties with their diagnostics, it is worthwhile to familiarize oneself with reading an audit: the DPE letter alone is no longer sufficient to assess the real cost of a purchase.
Old real estate prices: understanding the recent correction before buying
Competing guides talk about seasonality (buy in winter, sell in spring). This is a secondary angle compared to what has happened in the market over the past three years.
The Notaires-INSEE index of old housing prices has declined every quarter between mid-2023 and the end of 2024. The low point reached about -3.9% year-on-year in the third quarter of 2024, the first annual decline since late 2015. After a decade of nearly continuous increase, this correction surprised many homeowners who were counting on an automatic capital gain.
Since the first quarter of 2025, prices have stabilized with a slight increase of about 1%. We are talking about stabilization, not a new surge. For a buyer, this means that negotiating the price remains possible in the old market, especially for energy-intensive properties or those that have been on the market for a long time.
What this concretely changes for a sale
A seller who sets their price based on an estimate from 2022 risks seeing their property stagnate without offers. It is better to request an updated estimate based on recent transactions in the neighborhood, rather than on the listed prices of neighboring ads (which often include a negotiation margin).
For buyers, the drop of about 10% compared to the peaks of 2023 (according to Reduge and Valuo) offers a window, provided they do not confuse the listed price with the price signed at the notary. Notarial databases remain the reference for comparison.
Sales mandate and choice of real estate agency: what changes the game
It is often said that one should “multiply agencies” to sell quickly. In practice, a property listed with five agencies at five different prices sends a negative signal to buyers.
- The exclusive mandate engages a single agency for a defined period (usually three months). The agent invests more in professional photos, targeted visits, and follow-ups because they know that the commission goes to them if they close the deal.
- The simple mandate allows the property to be entrusted to multiple agencies, but each dedicates fewer resources to promotion. The property may appear as a duplicate on portals, with contradictory descriptions.
- The semi-exclusive mandate, less common, reserves the sale for one agency while allowing the owner to find a buyer themselves, without commission.
The choice depends on the local market. In a city where demand is high, a simple mandate may suffice. In an area where properties remain listed for several months, a well-negotiated exclusive mandate accelerates the sale.
Points to check before signing a mandate
Check the commitment duration and termination conditions. An exclusive mandate of three months with tacit monthly renewal remains reasonable. Beyond six months without results, one should be able to change agencies without disproportionate penalties.
Also, see if the agency offers regular reports on visits: number of contacts, feedback from visitors, adjustment of the suggested price. An agent who does not communicate after three weeks has probably not prioritized your property.
Purchase offer and preliminary sales agreement: the clauses that truly protect
A written purchase offer morally commits the buyer, but it is the preliminary agreement (or promise of sale) that sets the legal framework. Two clauses deserve particular attention.
- The suspensive loan clause protects the buyer: if the bank refuses financing within the stipulated timeframe (usually 45 to 60 days), the sale is canceled and the deposit is refunded. Shortening this timeframe under pressure from the seller is risky.
- The suspensive clause related to the condition of the property (discovery of hidden defects, undeclared easements) allows one to withdraw if a serious issue arises between the preliminary agreement and the final deed.
- The legal withdrawal period of ten days after signing the preliminary agreement applies to any non-professional buyer, without justification required.
The notary drafts the final authentic deed. Their fees, often mistakenly referred to as “notary fees,” mainly include taxes paid to the state. The notary’s remuneration represents only a fraction of the total.
Buying or selling a property in 2025 requires mastering these technical and regulatory constraints even before stepping into an agency. The DPE, the energy audit, the correct reading of market prices, and the choice of the right mandate form the foundation of a transaction without unpleasant surprises.
