Bluetooth beacons positioning accuracy?

[MikeLemon]

I'm planning to use one of those beacon platforms:

www.ebay.com/.../352167746226

www.ebay.com/.../112493464451

for a close proximity positioning system now I'd like to know what would be the accuracy of such a system?

What could be done to improve it?(even if it means upgrading to nrf52832 or nrf52840)

[endnode]

Have you searched for the same Q&As on this forum? There are many and the conclusions from many people are roughly the same... accuracy without any special care will hardly be better then "is the object in this room or the next". There are of course methods how to make the system better, many academic papers, many commercial companies claiming sub 2m accuracy in almost real time BUT you need to understand that they have teams of 5-50 people working on it for 2-5 years, full time. Good luck.

[endnode]

Sub 10cm? Are you kidding? Google some B2B solutions for indoor positioning (for space optimizations, physical access control, airport navigation etc.) and you will see... not even these clowns claim more than 1m accuracy (and if they claim 1m it usually means in the lab whereas in the real complex buildings of office spaces or logistic halls/airports it's 2-3m in best).