Would open grade be suitable to use with GPS instead of renting a laser for surveying a new bin site? At the very least, we’d like to set a reference point and then see how much higher or lower various areas are.
I have a spare f9p, a laptop, various xbee parts (bt, wifi, usb adapters) and an ardusimple LR kit. Could I battery power the f9p and send the position & rtk correction to my laptop or even better an Android app?
Want to start Monday.
Isn’t opengrade an overkill for that task. An F9P at RTK and the rover with u-center would be ready well before Monday. 
You would have to make note of the height at the reference point and see if readings elsewhere are above or below.
It probably is, and 1" accuracy won’t be enough for the final pad leveling.
I think the Lefebure NTRIP app can do the job, will test later.
For survey only opengrade or u-center will be fine.
I used opengrade+ tablet+f9p+Lefebure app on my phone(ntrip at 5km)
Yeah, I had a very good accuracy (± 1/4") when surveying and levelling with a clear sky view but surveying near buildings seamed to be inches off even while displaying an rtk fix (probably just before loosing it)
So for final measurement (for a concrete formwork) I would only trust a laser.