As for one-time three-stage or phased, it generally depends on the wishes of the parties and the case. If some cases are very minor, or you don't know much about the lawyer's working ability and attitude, you can pay by installments;
As for the success of the case, personally, it is not credible to say how far the case will go and how many sentences will be sentenced. First, handling cases and criminal law are the powers of state departments, and it is unlikely to trade power and money now, especially in criminal cases, which involve three departments, public security, procuratorial work, courts and lawyers. At least I don't believe it. Second: before meeting or seeing all the case materials, the promise is even more unfounded;
If a lawyer promises, tell him to write down everything he promises.