3 sims 1 account (data only for dash cam)

I have 3 dash cameras & needing a data sim for each camera. Needing around 10gb per sim. 
what’s the best, cheapest and easiest way to have 3 sims and also to be controlled via one account? 

I have 2 now, using 2 different email accounts which is a pain having to log in and out of both accounts. 

thanks