When you get caught trespassing on private property the first thing that will usually happen is that a cop will show up if someone calls the cops.
Then the cop will give you a trespass warning and advise you of criminal trespass and tell you that if you get caught trespassing again on the property that you'll be arrested the next time.
So at first you won't be arrested in most cases and will just be warned and then the next time you will be arrested if the cop is called back to the property and you're trespassing after being warned.
If arrested for trespassing you'll likely get bailed out of jail if you have the money to bail out and then be charged a $1,000.00 fine and possibly serve 6 months to a year in jail if sentenced.
So if you're caught trespassing do not go back and trespass as it's not worth serving the time in jail over and paying the fine.