ow-Cost Bluetooth External Sensor Prototype

I’m looking for someone to build a low-cost prototype external sensor unit for my GrowlerZ iOvilus project.
The idea is a small Bluetooth sensor hub that connects to an Android phone/app and sends live readings from external sensors.
Prototype requirements:
ESP32-C3 or similar low-cost Bluetooth/USB-C microcontroller
External EMF/magnetometer sensor
Ambient temperature sensor
Humidity sensor
Barometric pressure sensor
Light/lux sensor
Battery powered if possible, or USB powered for first prototype
Simple 3D-printed or off-the-shelf enclosure
Live sensor readings sent over Bluetooth BLE
Basic documentation so my app developer can connect it to a Flutter Android app
This does not need to be a finished commercial product yet. I’m looking for a working proof-of-concept prototype first, keeping the cost as low as possible.
Please let me know:
Whether you can build this
Estimated cost for a prototype
Estimated timescale
What parts you would recommend
Whether you can provide firmware/source code
Kind regards,
Stephen Lewis
GrowlerZ Paranormal Tools