Never said a prison sentence, he's in a drunk tank for a misdemeanor and people have to generally post bail for them too, to guarantee they show up to their hearing. Dan has no connections to friends or family or true business ties to the local community in Chicago. He might be a flight risk, so even a $500 bond, through a bail-bondsman while you give him $50, and 10% is pretty normal, especially in a misdemeanor case like public intoxication, loitering, and trespassing. When you get a bond, you generally don't leave the area before the trial, which could be backed up, due to the sheer case load in Chicago. Lester sure saw something at their door which let him know he had a key to the door now and would get in. Sarah and Dan are financially in a tough spot and Sarah would not want to lost their house, of for no other reason, up-rooting her daughters and possibly having to change schools, both things a lot of parents try to avoid.
I didn't mention anything that unrealistic.
He set Dan up, he works in Middleton, with Sarah, and has some way into their house. Hell, from the deal Don was making for Lester's pay for fixing the worm he introduced into the hospital's computer systems, he could most certainly take a large chunk out of the owed mortgage, if not all of it based on his hacking, his computer skills, his porn making, etc.