What everyone is leaving out is your time. Figure that into the mix. If you go micro but then do elaborate things to avoid paying the occasional slightly higher fees, you are wasting alot of time, and time is money.

Make sure it is worth all the time it takes to open second emails, second PP accounts, send some items here, some there, never send combined invoices, etc. If you are going to save 30 cents while wasting 45 minutes, that is not worth it.