Scam CBD sellers tend to manufacture low-grade oils via ethanol (or other solvent-based) extraction, in what is little better than trying to do it yourself in your basement. The result is a liquid that contains a little CBD (along with some other cannabinoids and terpenes), but not in the quantities needed to be effective in terms of any legitimate medicinal function. Moreover, these solvent-based extracts can contain unnecessary and potentially harmful components — after all, scam artists are not going to reveal the REAL ingredients, are they?
THC free: If it's important to you to sell a family-friendly product that anyone can use, look for an oil that is THC free. THC is the cannabinoid that makes you high. As a simple rule of thumb, if a brand isn't promoting that their product is THC free, it isn't. The process to remove THC from CBD oil creates a much higher expense for the manufacturer, so many brands choose not to do it. It may cost more, but in my experience, it's worth it to provide the option of non-psychoactive product.