Beginner Question: Best Hardware

Hello, I’m new to openhab and would like to integrate three temperature/humidity sensors via radio (maybe 433Mhz?). One outside and two in my house. My Questions:

  • What is the best reciever for a beginner on a raspberry?
  • What kind of temperature sensors are the best for me? Maybe there exist already a set with transmitter/reciever and the sensors working fine with the raspberry?

I’m also thinking about to control wireless my floor heating in the sauna. Just once a week I switch it on, not reguraly. I would need a remote control switsch that I also can switsch manually.

Thanks Patrick

Take a breath and have some long-term considerations first.
As openHAB provides many interfaces, you can use various different technologies at the same time to accomplish what you want, and there’s way too many possibilities to list 'em all. But as you’re considering yourself to be a beginner, you should avoid Arduinos and other stuff to require DIY in HW and SW. 433MHz radio, while cheap, comes with a couple of issues that I’d avoid as a beginner. Remember you can still add more technologies later when you’re more familiar with Pis and openHAB.
And you’re (for now) just planning on a couple of devices, but you have ideas to extend your smart home. So you should look for a flexible, reusable and possibly scalable radio solution. I’d vote for readymade ZWave products.
Get a ZWave controller such as the RaZberry card for your Pi or the Aeon Gen5 USB stick. Use it as the transmitter/receiver on the Pi side. There’s many ZWave devices to provide remote switching and temperature sensing, most are ~50€.
A popular switch is the Fibaro FGS-222. Or use the Qubino Flush Relay, that’s a switch where you can add a 1-wire sensor such as a DS18B20 for temperature sensing. Those DS18B20 sensors are 1€ on *bay and used in most products and DIY solutions. For temp + humidity, you could use a Aeon Multisensor 6, I’m also using it in the room where I do my laundry and where the entrance to my sauna is.

Thank you for your considerations. They are very helpful!

Or a bit of a DIY if you ready to spend more time -