I would like to use OR for my HA project.
Can someone tell me how I can use it to monitor/control lots of descrete I/Os cheaply?
Maybe some I/O boards/modules...? Looking for some DIY solutions
Thanks for any help
Too hard?
Never too hard 
Maybe you could expand your question a little?
Do you want to control?
What control modules do you have in mind?
Which protocol do they use?
At a guess there are over 4000 users of OpenRemote, each with unique hardware combinations, so you could potentially get 4000 different opinions of "what is best".
But I doubt that the word "cheap" will feature in many people's answers. 
Ok...I have looked at plenty of HA systems over the years and I have noticed the cost has been increasing more and more. Their operation and functionality have increased even more to more than match the increase in cost.
I have been looking at the 1-wire system. It appears to me as an ideal system to create lots of I/Os cheaply, a few dollars per I/O.
I no nothing about coding/Linux and I'm having trouble just installing the OWFS programs onto my Raspberry Pi 3 so any help with this would be great.
I have OR working.
Thanks