I imported the BOM for the tracker to Mouser and it looks like it's around $100 in components for one board. It looks like the boards with ENIG finish and filled and capped vias would be ~$40 for five boards + ~$17 shipping to the US from jlcpcb. ~$15 of the board cost comes from the via covering.
The most expensive component, the DWM3001CTR13 Ultra-WideBand module, is $37.77 in single quantities. I don't know much about about UWB, but I wonder if instead putting a BLE beacon on the tracker and using a chip supporting Bluetooth direction finding on the home station could allow the tracker to be a bit smaller and cheaper at the cost of some localization performance for the indoor mode (actually I just saw someone already brought this up in the project Slack).
This isn't including the Home Station part which doesn't seem fully documented yet.It looks like there is more discussion on the project Slack.
In a power supply you can sense your output voltage with a differential amplifier between the positive and negative outputs that way the voltage drop across your current sense resistor is not included in the measured differential voltage. Alternatively you can use high-side current sensing where your current sense resistor is before your positive output. You can also use a differential amplifier for that, but there are purpose made current sense amplifiers which are probably best.
The most expensive component, the DWM3001CTR13 Ultra-WideBand module, is $37.77 in single quantities. I don't know much about about UWB, but I wonder if instead putting a BLE beacon on the tracker and using a chip supporting Bluetooth direction finding on the home station could allow the tracker to be a bit smaller and cheaper at the cost of some localization performance for the indoor mode (actually I just saw someone already brought this up in the project Slack).
This isn't including the Home Station part which doesn't seem fully documented yet.It looks like there is more discussion on the project Slack.