While creating a BoostOffer on Warden, a veCRV holder approves the Warden contract to create veBoost on their balance, then set a price (in CRV) for 1vecRV/week, a percentage for the minimum Boost size a Buyer must take on their offer, and a 2nd percentage to set what is the maximum part of their veCRV balance Warden can create veBoost with (if the maximum is set at 50%, only the half of the veCRV balance is available to create veBoosts, the rest will always be used for the owner boost). And while there is no veBoost bought based on your BoostOffer, the veCRV holder keeps all it's balance as a personal boost.