Can I please get help in legal concepts/elements that could be good for a contract for the building of a home? (NOT concepts for the contraction creation like offer, acceptance, bargaining... I'm needing actual contract terms)

SCENARIO

After successfully rehabbing the Peace Cross and beautifying the area around it, Brady and Roger received an influx of business inquiries. New customer calls came in for them to build, renovate and make beautiful spaces. With each new customer, contracts were required. One day a new client came in to inquire about the building of a state-of-the-art castle. It was an unusual request, but Roger felt they could meet the customer's goals. Their business is based in Pocomoke City, Maryland, which is about 20 minutes from the client's prospective home.

The customer's name is Elsa Winters. She lives in Loveville, Maryland. But, she wants Brady and Rogerof Old Time Restorations to build her a castle in Arendelle, Maryland. She wants the castle to resemble ice. Obviously, ice would melt in Maryland summers, but she has a vision of floor-to-ceiling windows that shimmer in the sun. She wants the castle built in the mountains, overlooking Chesapeake Bay. Assume that all permits, engineering studies, and licenses have been approved. The plans for the castle are complete. She wants the house to be a deep blue on the outside, filled with shiplap, lots of windows, and solar lights. She wants white and blue to be the interior colors. She wants radiant heat floor heating, water sourced from the bay, an indoor pool, and an indoor herb garden. She also wants a room that is soundproof with marble flooring so she can work on her ice-making skills without bothering other people in the castle. Of particular importance, she wants a large white cross in the center of her ballroom. She says it needs to look like the Peace Cross because she had family members who served in that war. It is important that her parents' names are engraved on the cross. Roger and Brady are confident that they can make this cross happen because of their recent renovation and repair of the cross.

The jurisdiction in Maryland. The project must be completed in 9 months. The complete price for the project is $2.5 million. The contract date is April 15, 2021, and completion must be made by January 15, 2022. For each day that the project is not completed, $5,000.00 is reduced from the contract. It doesn't matter if weather, delivery, or technology prevents completion. However, an act of God would not cause this clause to kick in. Time is of the essence because Elsa's sister, Anna, is marrying her beloved Sven and the new castle will be the venue. Any customizations or changes to Elsa's wishes must be put in writing. If there is any dispute, the parties have agreed to use binding arbitration.