Hello everybody,
I have a fairly simple question: How to start with openHAB hardware-wise? =)
Software-wise I am all good. I installed openHAB on my Raspberry Pi and played a little bit with its configurations. I connected my LG TV, my Chromecast and some simple network devices (phone, laptop). I set up some rules like: Start streaming on Chromecast -> that turns on the TV -> then open Netflix App. I made a sitemap and everything worked very well. I am familiar with java, javascript,… so programming/scripting should not be a problem here.
Now some details about my question:
What I have: Besides the mentioned Raspberry Pi there is basically no hardware. 
What I want: Control light, electrical blinds and later maybe underfloor heating. I would like to set everything one by one, starting for example with the living room. The old light switches should work side by side with the possibility to change the light with the mobile phone. There are some cross circuits and changing circuits that should still be working. I also would like to control stuff like the TV, but that already kind of works. 
What is a good way to start hardware-wise?
At the moment, I tend to buy some hardware from Homematic (german websites, only two allowed, cause its my first post):
http://www.eq-3.de/produkte/homematic/licht/homematic-funk-sender-2-fach-fuer-markenschalter-unterputzmontag.html
http://www.eq-3.de/produkte/homematic/zentralen-und-gateways/homematic-zentrale-ccu-2.html
Are there any other good or maybe better options to start? How have you guys started? What went good, what went bad? As far as I read it, it won’t be easy to set up the cross circuits or changing circuits with homematic.
Any help, small tips or questions about my planned setup are appreciated.