This one works extremely well. You can make a smaller version of this, using a smaller tote or even a 5 gallon bucket which I've seen many people do. If you go the five gallon bucket route, and you only need six to eight sights, you should be able to do it for $50-$60.
The pump would be your biggest expense (that is, if you alrady own a drill). The hole saw bit (for drilling the clone collar holes) can be pricey too, so you'll need to shop around for that.
I would definitely make the biggest one that you can afford, that way you'll have the capability of making larger numbers of clones in the future if needed.
https://www.420magazine.com/community/threads/diy-50-site-aero-cloner-for-under-100-00.135077/
You can also make a cheaper version of this without the aeroponic sprayers, and just make it like a dwc. Then, instead of a waterpump you'd only need to use an air pump with a few good air stones to make sure the water is extremely oxygenated. That way, when the roots hit the water they won't drown themselves. They definitely work that way, but not quite as well as the aeroponic sprayer ones. You just have to make sure you have the water level just right so the aerosol bubbles come in contact with the stems/roots. With either one of these cloners, you would only use tap water or RO water, no nutrients or cloning solution.
*** After I posted this I kept reading the thread and saw that a lot of this was sort of covered, so I apologize for any redundancy. Hope it helps someone anyway.