Welcome to the club.

I'm using Broadlink RM4 Mini's I got off AliExpress. They've got a powerful enough IR signal that I've found I don't need them sitting way out in the open and obvious. One is tucked behind a TV and not quite in direct LoS, one is behind, but it reflects off the wall just fine, another behind a bedside table.

For the integration/Climate control thing I'm using SmartIR. Configuring it is a bit weird, you have to put it direct into the configuration.yaml file unlike other integrations.

    smartir:
      check_updates: true

    climate:
      - platform: smartir
        name: Bedroom AC
        unique_id: bedroom_ac
        device_code: 1293 
        # https://github.com/smartHomeHub/SmartIR/blob/master/docs/CLIMATE.md#available-codes-for-climate-devices
        controller_data: remote.mini4c_bedroom
        temperature_sensor: sensor.airquality_ikea_bedroom_temperature
        humidity_sensor: sensor.airquality_ikea_bedroom_humidity
        power_sensor: binary_sensor.contact_bed_ac