# Search criteria

To optimize the sustainability advice the API is able to process a search criteria function next to target energylabel.

#### Search criteria - "search\_criteria"

The search criteria used for the sustainability advice. The different criteria can yield different results. 

* Syntax: 'search\_criteria' 
* Required: No
* Values: Integer, 1 to 4
* Default: 3 
* Description: 
  * 1 = lowest investment costs 
  * 2 = lowest energy costs 
  * 3 = highest return on investment
  * 4 = lowest BENG2 score (highest energy label)

**User input-based result selection**

The final result is based on the user-defined criterion, along with any set restrictions, such as maximum investment or target energy label.

* **Max investment**: Filters results where the total investment required is below the set limit.
* **Target label**: Filters results where the energy label meets or exceeds the target value.
* **Strict target label**: If "energylabel\_strict": 1, only results exactly matching the target label are returned.
* **Criterion-based selection**: After filtering, the criterion determines the final result.

Criteria options:

* **1: Lowest investment cost** - Result with the lowest total investment required. This results in measures which will generate just enough BENG2 improvements to meet the target energy label .
* **2: Lowest energy cost** - Result with the lowest annual energy expenses focusing on measures which reduce the monthly energy bill the most.
* **3: Highest return on investment** - Returns the result with the highest financial benefit within the energy label range.
* **4: Lowest BENG2 score** - Property with the lowest BENG2 score, indicating the best energy performance.


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# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.altum.ai/english/sustainability/sustainability-api-v2-apartments/search-criteria.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.