Hi, here´s a short post about a DIY temperature sensor I build for a relative.
The main parts were ordered in bulk on Amazon, and the “software” was “written” in ESPHome on the Raspberry PI that is running HomeAssistant.
For more detailed instructions and the code have a look at the Wiki Page
If you are interested in more in-depth instructions or have any questions please feel free to leave a comment below or on the wiki page.