MDT at Paragon Home Inspections, LLC wrote:
1)You need EPA certification to service the unit.

2) If it's releasing more than fifteen percent of its charge over the
course of a year, the EPA requires the system to be repaired rather
than repeatedly recharged.

http://epa.gov/ozone/title6/608/608fact.html#techcert

Michael Thomas
Paragon Home Inspection, LLC
mdt@paragoninspectsDOTcom
847-475-5668

Michael - Do you have a link / citation for your 'fifteen percent loss
per year requires repair' statement? It is my understanding that there
is no such EPA requirement for appliances containing less than 50lbs of
CFC/HCFCs.