As a reasonable finder of fact could determine that the agreement to keep the piano in the warehouse was a consensual agreement that ultimately benefitted both parties, and under state law, claims regarding bailments can be subject to either the contract-claim or tort-claim statute of limitations, there exists an issue for trial as to whether the shorter limitation term applies.
Possession is sufficient for rebuttable proof of ownership at the time of the creation of the bailment; ownership, and therefore the validity of the bailment, therefore presents a genuine issue of material fact for trial.
A reasonable juror could find that the acceptance of the piano created an enforceable contract, as the owner of the piano saved storage costs, making for sufficient consideration. The term of the contract need not have been definite; possessing it until it was requested by the owner would be sufficient.
Genuine issue for trial as to ownership, given corporate succession beforehand; employee's statement that the piano would be "all yours" if picked up states a claim for transfer of ownership.