A very reliable call sign is the "Limp" move. I would say that 99% or more of regular cash games only use the Small Blind limp, so if you see a player using that move from the other positions, his chance to be recreational is huge! Stay tuned.
The size of the bet can also be a strong call, nowadays almost no regular raise gives more than 3x from any position on the table, so if you see an open raise of 3.5x or higher, it will be very interesting to give a better check in the player, because the chance of it being recreational is very high also.
So I have to analyze a lot of the types of hand that I put into a play, I usually in cash, follow the rules mentioned above, when I am in a tournament, I play most of these hands, without much concern because I consider cards strong to face the opponent