Would you sue?

My son and is dad did a construction job for this lady. She's worked with them before in a hospital do they did no contract because "She's an old coworker". She started being difficult right away so they granted her a discount, she was still unhappy so they went out of their way to do extra stuff. Now she's saying she doesn't like it and verbatim texted "Well too bad, I'm not paying you haha".

My son is furious and went into the workforce to fill out a wage dispute.

Thing is, this lady shot her husband, went to jail and when she got out boasted to her ex's family and harassed them for a while. She also used a machete on a guy, was trying to slice him up. She's a psychopath! I'm just wondering if it's worth it to go through all this trouble for a few hundred dollars.

We did learn afterwards that she does this ALL the time, has people working on her house then complains and refuses to pay, that's why all the work she's had done has been cost free. She implements her own little system and never gets repercussions. Would you sue?