I'm a pretty easy-going trader.  As long as the values are pretty close I generally won't have any issues. 

I prefer to ship with less expensive means.  For smaller value trades I will ship in a protective sleeve placed in a hard top loader and sealed in a plain white envelop.  For higher value trades I will ship in a top loader and bubble mailer with a tracking number.  I try to get trades in the mail by at least the next business day, but if it's going to take longer I'll be sure to let you know.

Like most folks on here I've got a couple of boxes of commons and uncommons so if there is something specific you need just ask.