Recommended low-power models
Maybe look at what Gekkoscience offers, or the Bitaxe project. Or what any ASIC brand is producing but with using only a single hashboard. Like a single hashboard of S19 for example. Generally, you could focus your research on hobby/home mining.
And for next time, if there are any, you might try to be more precise and clear in your questions, could be nice.
I used some gamma 601. You mean, it can also convert it to solar mining? Is this cheaper? My current 601 has relatively weak power, at just 15W.