At this point I'd like to start addressing the different scenarios that COULD happen from this point towards the moment these  machines are hashing.

For example, we need to consider the possibility of additional fees and how they are handled and what CoinHoarder is comfortable with.

Should we have a wallet set up, where we could put bitcoin to cover any unexpected fees, or is it all covered in the 3% hosting?

In a perfect world unexpected things never occur though, but we're not living in one, so I think we need to do some kind of a threat analysis.