Under the COVID-19 Ontario Regulation 82/20, that model home/inventory home is a part of the builder's supply chain and therefore can generally be sold and open to the public but operating as a retail operation for the builder, and therefore should adhere to the requirements of businesses that engage in retail sale of items to the public within the regulation.
OHBA has prepared a guidance document which may be useful in the development of your protocols for operating a model home.
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