My brother in-law has been doing Christmas lights for some years now, and I think he may have caught the bug. 
Until now, he has only been using store bought lights. However, his latest acquisition was some Coro Props, which he proudly showed me. After seeing some online videos, he wanted to make them sing, but when I told him that he would need to step-up to Pixels to do this, he was understandably a bit worried.
Anyway, he’s already gone out and purchased some Pixels, but as I tried to tell him, that’s only the biggening of his journey, not to mention the upcoming extra costs.
Can anyone recommend a good entry level controller, and where to get it (new or second hand would be fine). Or, would a Raspberry Pi with a Pixel Hat be the cheapest way to go?
Thanks in advance for your advice and guidance on this issue.
P.S. If anyone has an old Pixel Controller they no longer need, please let me know.

Until now, he has only been using store bought lights. However, his latest acquisition was some Coro Props, which he proudly showed me. After seeing some online videos, he wanted to make them sing, but when I told him that he would need to step-up to Pixels to do this, he was understandably a bit worried.
Anyway, he’s already gone out and purchased some Pixels, but as I tried to tell him, that’s only the biggening of his journey, not to mention the upcoming extra costs.
Can anyone recommend a good entry level controller, and where to get it (new or second hand would be fine). Or, would a Raspberry Pi with a Pixel Hat be the cheapest way to go?
Thanks in advance for your advice and guidance on this issue.

P.S. If anyone has an old Pixel Controller they no longer need, please let me know.