Buying a house basicially invites many people into your personal life for a few months. I lost count of the amount of bank statements I had to fax somewhere, all with notes explaining several deposits. Mind you, the notes wern't enough, it was to point the person to the other paperwork included, like proof that one $1500 deposit was actually my tax refund, then a series of deposits totaling $9000 was my stock selloff.

It was definitly a big mess, but worth it in the end. I am sure 100k down that was not showing up anywhere in your history would raise quite a few flags, potentially enough to deny a loan for the rest of the house.