MD doesn't require shit for mopeds. No titling, no registration, no fees, no plates, no nothing. You don't even need to wear a helmet. All ya need is a driver's license or a moped operator's permit. No notarization was required on my Bill of Sale.
The most important thing was a copy of MD vehicle exemptions. They made a copy of this at the title agency. It basically says MD doesn't require shit, in fact you CAN'T register or title a moped. This is considered your leverage that PA can't do anything about but get you a title.
There were a few forms, and I've heard that these forms are no longer in circulation, but I don't know if that is true. You'll have to do some homework on that.
As far as costs...You have to pay 6% on whatever the buying price of the moped - $100 = $6 in state tax. You have to pay insurance which is anywhere from $5-$15 a month. There was a $24 title processing fee, a $9 registration fee, and a $40 fee for a tag and title agency to handle everything for me. That can be omitted, but at the time, it was worth every penny to have THEM haggle with the DMV.
I think that was it for the fees. There might be a plate fee in there, too, but I can't remember. Exluding the price of the bike and insurance, you're looking at about $50 without the help of a tag and title agency.
Email me if you have anymore questions.