Start with the report identity
A percentage without context is incomplete information. Ask for the whole document rather than a cropped screenshot. Check the VIN, date, mileage, issuer and method. Establish whether it concerns the car being sold and whether battery or software work has taken place since the test. Keep the document separate from the seller's explanation. A familiar logo or professional-looking file cannot replace the information connecting a result with the actual vehicle.
Charge level is not battery health
The displayed charge level concerns energy available at a particular moment. A health assessment concerns condition or retained energy relative to a reference. They answer different questions. A fully charged battery is not automatically equivalent to a new one, and the dashboard's estimated driving range is not a capacity report. Ask what each indicator means, how it was obtained and which battery version it describes before comparing two figures. Do not assume that every provider uses identical terminology.
Compare comparable methods
Results may come from management-system data, a manufacturer procedure or another provider's test. Different methods are not automatically interchangeable. Ask about the reference value, conditions and limitations. Tesla's manual, for example, distinguishes an assessment using vehicle data from a dedicated test that may not be fitted to every vehicle. That does not establish a universal procedure for other models. Follow the instructions applicable to the actual car and the test provider instead of borrowing a process from another brand.
Consider the whole system
An energy-retention result cannot describe every aspect of physical condition, cooling and charging. Ask for current warnings and relevant repair records. Do not open the battery or improvise tests on high-voltage circuits. Where a concern exists, use a qualified specialist who can explain the scope and remaining uncertainty. An agreed charging session may add practical information, but one peak-power figure or short session cannot establish the condition of the entire system.
Relate the result to your routine
Consider your regular route, speed, seasons and stops. Use editable assumptions to assess whether a comfortable reserve remains. A health percentage cannot promise motorway range. Cars with similar reported percentages may have different battery sizes, efficiency and charging behaviour. Check your actual access to charging at home or work. A car offering sufficient practical flexibility may suit you better than another selected solely for the largest number shown in a gallery.
Read the actual warranty
Check the document applying to the VIN, its start date, time and mileage limits, conditions and claim process. Defect cover and capacity commitments can be expressed differently. BMW's published information, for example, varies by model and generation; do not extend its terms to another make or market. Confirm transfer arrangements and past repairs. A warranty threshold is not a complete purchase criterion and does not establish that a particular claim will be accepted without assessment.
Ask decision-changing questions
Ask when the test was carried out, who can explain it, whether warnings remain and what documents support declared repairs. If reports disagree, investigate their methods and conditions before requesting interpretation. Separate the recorded result from the conclusion being offered. Avoid treating “as new” as an established fact when the evidence is a screenshot. The advertisement, document and conversation should describe the same vehicle. Keep inconvenient information instead of removing it to preserve an early impression.
Keep a dated reference
After purchase, retain the report, mileage and repair records for future comparisons under explained conditions. Do not repeatedly run demanding procedures simply to watch a daily percentage. Follow the manufacturer's charging, use and testing recommendations. A seller-uploaded report on Carletta should be read with its provenance and limitations. Uploading a document does not mean that the platform independently inspected the battery. Use the records to guide questions and obtain confirmation before deciding.
When two percentages disagree
Do not automatically choose the larger figure. First check whether the reference, method and battery identity are comparable. Ask the provider to explain the difference and any requirements for repeating the assessment. If the explanation remains unclear, preserve both results and consult a suitably qualified specialist. A newer report may be relevant, but its date alone cannot establish a better method. Your objective is to understand what can reasonably be said about the actual car, not to select whichever document offers the most convenient number. Include unresolved measurement differences among the remaining purchase questions.
