Does anyone out there know how much a P3S can carry (without permanetly damaging the motors)?

Why would it damage the motors ? It either flies or it doesn't.

As to how much it can lift ..... ??

Nigel

Was not designed really to be a cargo carrier.  True, you can lift and move things around with it (like a pound or so), but if the FAA finds out, you might get slapped with a huge fine.
http://www.cnn.com/2014/01/31/tech/innovation/beer-drone-faa/

It can lift over 2 pounds. Although you can kiss off that 23 minutes of flying time.