How to demolish a house?

If you want to start a new house over to help make your next house cheaper you can sell all of the items in each room, then sell the individual rooms themselves. Then, if you want to demolish the house or lot, you need to move any existing Sims out of the house or delete (abandon) them. Once that is done, you can click the lot with the house removed and you will be invited to add a Sim etc... If you scroll to the right there is the option to demolish house, select that, and then you can build a new house on that lot.

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