I recently had an encounter and am now regretting it very much. Very risky and stupid behavior. Hopefully my stupid actions and the lesson I learned can prevent you from making the same mistake.
Not safe. Very risky for multiple reasons. Cops use backpage to set up sting operations. You also have no idea what kind of risks these people can set you up for. They may have STD's, they may be drug users. They may bring someone along with them to steal your money and hurt you. If you absolutely must do this, just get a handjob.
1. Impossible to tell you
2. Don't get an escort or yes just be masterbated
3. Oral, vaginal and anal sex even with a condom runs a risk, very low but still a risk.