I am currently evaluating if LAVA is the right tool for testing our custom flavour of a Raspbian Linux distro. The DUT is going to be a Raspberry Pi3 and I was trying to set it up in a minimal way using another Raspbi3 as a Server & Dispatcher (although first it seemed to work fine, when I followed the LAVA documentation and added the stretch backports sources in the apt list, my whole system crashed because of the depedencies). 

What is the best way to get a minimal setup running? I am also interested to know the hardware process (ideally everything we want to be automated). So, should the DUT be connected via a USB2serial cable?


Other than that should that be connected to an SD multiplexer that burns the resulting .img after Jenkins finishes checking and generating it? 
Documentation is a bit tricky to go through as it covers many cases and there's not a simpler minimal tutorial. Also all the online blogs/posts seem to work for LAVA V1 only as a few things have changed.

So it will look something like this:
Linux .img (to be tested) -> SD Multiplexer(?) - DUT - USB2Serial -> LAVA Server & Dispatcher
                                                                         LCD Screen

Are there anywhere some sample tests so I can get an idea of what I will be able to do? (Had already a look at the linaro .git but those seem 'too' basic; probably I've missed smth).

Thank you all for your help.