Story ideas

I know that there are gaps missing in the two stories that I already have, and I am thinking  of ways to fill those gaps. The first story will be about blackmailing, the next one with the kids will be about revenge, and the last story(which I am currently gathering models for) will be about 2 women scamming a guy out of his money. In the first story I am missing the murder scene, and the scene showing that he is blackmailing him. The second story I am missing the what the revenge is for, and I leaning toward the murder of a sibling  over wrongfully putting a sibling in jail.  For the one where the women are scamming some hapeless guy out of his money, I am unsure under what circumstances and where the money is coming from.  For the intro blackmailing one the one being blackmailed will get a note on his desk at work delivered by the femme fatale(the secretary), which explains that he is being blackmailed.  The death scene for this will be easy because it will be a head blow that kills the blackmailer. After he falls the femme fatale and the one being blackmailed will carry out his body and ditch it somewhere. Basically I am going to use the vacant plot of land next to my house for them to dump him. So for the second story I have to shoot the revenge and the chase scene from both sides. For the last one i am thinking about it being a health insurance scam or investing scam.