Gateway advice required

Cheapest option is not not get a concentrator card. Get a TTIG or something like an LPS8. Apart from hardware issues that would be warranty cases I am unaware of issues with either of them.
You can build your own gateway with a concentrator card and a RPi but that is riskier with regards to getting and keeping it working. (I have > 20 gateways, a mix of different vendors and hardware, at least 10 RPi based)

Not sure how poultry factors in or where you got the idea that concentrator cards being sold now to go on the top of a RPi wouldnā€™t work. How do you think the rest of us build Pi based gateways?

There are various generations of chips but thatā€™s almost all about power consumption but the newer ones are a tad more sensitive.

If you want to attach a device to a Pi, youā€™d better be clear what that might mean, particularly if the device is a device and not a radio. And if you do manage 8 radios co-ordinated across 8 Piā€™s, please take pictures!

In this context there is no old old only earlier, earlier, the original SX1301 and the derivative SX1308 still work, the devices and the specs - even though they have seen some evolution they follow the same basic elementsā€¦key is get a LoRaWAN concentrator card of any generation do not even think of trying to concoct something from devices (trust me you wont be able!)ā€¦if its any comfort I still build & configure gateways using Piā€™s and SX1301ā€™s - done 2 so far this month alone, as well as using '08ā€™s & 02ā€™sā€¦.just go crack some eggs and get on with it! There are plenty of tutorials, manufacturers guides and videos showing how too - even the old ones using TTNv2 remain valid from a spec, operation and fundamentals perspective - just make sure you point at the V3 (TTS(CE)) servers and adapt to what you see in the console when registering and setting up.