Your son needs to understand what a POA is. He needs to sign the paperwork assigning you. I think he needs to be present and the lawyer explaining to both of you what is involved in a POA. Too many posts on this forum where people didn't understand what a POA entailed. Id your son cannot make an informed decision he can't assign a POA.
POA is a fairly standard document and could most likely be well executed by any licensed lawyer with specialties in estate planning and/or elder/disabled law. There may be an advantage in having an attorney licensed in Massachusetts draft the document to take advantage of any special requirements or advantages available in Massachusetts.
I like staying with the one I know so I would probably ask your Maine lawyer if he or someone in his firm is also licensed in Massachusetts. If not, I would ask whether he would be more comfortable drafting the POA or overseeing the hiring of a Massachusetts licensed attorney to prepare the draft.
If you think you may need additional legal services in Massachusetts, then I would consider using this time to search for a good Massachusetts attorney.
I like staying with the one I know so I would probably ask your Maine lawyer if he or someone in his firm is also licensed in Massachusetts. If not, I would ask whether he would be more comfortable drafting the POA or overseeing the hiring of a Massachusetts licensed attorney to prepare the draft.
If you think you may need additional legal services in Massachusetts, then I would consider using this time to search for a good Massachusetts attorney.