Contracts

If you sign a lease and change your mind within 3 days, can you get out of the agreement?

I have been bringing craft items to a local consignment store. I originally signed a contract stating that I must pay a monthly fee and update my items. They re-mark my items for 25% more than my asking price. Over the 10+ years I have brought my items to the store, the store has had 3 different owners. I have never signed a different contract or been asked to do a new inventory with the new owners and had no input into the sale of the business. Now I have terminated my association with the store. Several items are missing-$450 worth plus $40 worth of broken items. The current owners paid me $175 for some missing items, but their lawyer says they are responsible only for the items which I brought in since they took ownership. I thought since my contract is with the store, it shouldn't matter who the owners are-the current owners should be responsible. There is no mention of reimbursement for lost/stolen items in the contract. Is there any way for me to get my money ?

I am starting a business offering creative designs for the home and office. Some of the items (plants, silk arragements, and other commissioned art pieces will be incorporated into the designs. I will research other artists work, commercially or personally and need to have a contract stating that there are no returns, who is authorized to approve, and payment terms, and fees for my services etc.

What is the difference between a technical breach and a material breach? What is the Doctrine of Mutuality?

Is there a rescind / cooling off time on a purchase of a new vehicle?