Co-foster: rescue holds titleWe stay the legal owner the whole time. If the pair splits, the dog comes back to us — not to a fight.
Co-adopt: one named ownerTitle goes to one person, never both. The second household's rights live in the agreement, with a buyout price set on day one.
First right of refusalTravel, illness, a late shift: the other home gets asked before a sitter or a boarding kennel.
Shared vet authorizationBoth homes can authorize emergency treatment up to an agreed ceiling without waiting on the other.
Named tiebreakerOne person, agreed in advance, decides when the two homes can't. Usually the placement coordinator.
Cost ceiling and split50/50 by default. Anything over the ceiling needs both signatures before the card gets charged.
Return clauseEither home can hand the dog back, no penalty, no questions. That clause is why dogs don't end up on Craigslist.