Nobody in this day and age gets intimidated by solicitors letters......You will always find a solicitor who will write whatever you want in a letter but to what end? If you are being harassed, then call the Guards and let them know. At least you will have a history of contacting them if things do escalate. You need to protect yourself. Going down the civil route as a first step is a waste of money and time. He might not listen to the Guards, the Guards might not do very much and tell you that they are limited to what they can do but at least you are now on the record. Add to it every time if there are further incidents so there is an official log. If it escalates or doesn't stop, then you are in a stronger position to take action. At the very least, the guards will be able to advise you on options...