Except MQTT No problem for the other feature (200 m2 is small area so the Denna can work with only one battery without issue).
The real question is "a reasonable budget?",for only 200 m2 maybe a new commercial mower can do the stuff but
To know the real cost:
Try to make a list in Ardumower shop of what you want and i tell you what is OK and Not.
You don't need GPS ,IMU,BT module from shop.
In China you need to order RFID receiver with ESP32 and cards, 2 waterproof Sonar sensor, GY88 IMU,Raspberry Pi3B+(If you want MQTT maybe the ZERO W is not OK)
The real question is "a reasonable budget?",for only 200 m2 maybe a new commercial mower can do the stuff but
To know the real cost:
Try to make a list in Ardumower shop of what you want and i tell you what is OK and Not.
You don't need GPS ,IMU,BT module from shop.
In China you need to order RFID receiver with ESP32 and cards, 2 waterproof Sonar sensor, GY88 IMU,Raspberry Pi3B+(If you want MQTT maybe the ZERO W is not OK)