They would need to know support and resistance but remember those are based on price, but of course, they would include where volume came to support price and resistance levels. Lower volume stocks by their nature are slow moving and much easier to determine SnR levels than a quickly moving stock but again, this is all algorithmic so hunting and pecking trying to determine those levels is a thing of the past, for the most part. Rather than focusing on stop levels investors should learn how to properly use stop orders.
News 
Market Data 
Discover 
