These houses are completely baked when you open the blender file.

However: you might want to edit the lighting or change the layout of the house.

In this case it needs a rebake:

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To rebake the day version:

Change the HDRI to ''(for eevee bake) Blue Sky''

Then turn off the camera icon of the ''Eevee Not Bake'' collection in the outliner.

Scroll down the render properties and press Bake Indirect Lighting (this can take a few minutes to several hours, depending on the size of the house and your hardware)

After its done, turn back on the camera icon for the ''Eevee Not Bake'' collection on the outliner.

Change the HDRI back to ''(For cycles) HDRI''

Make sure to save the file, the lighting data gets saved when you save the file.

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To rebake the night version:

turn off the camera icon of the ''Eevee Not Bake'' collection in the outliner.

Scroll down the render properties and press Bake Indirect Lighting (this can take a few minutes to several hours, depending on the size of the house and your hardware)

After its done, turn back on the camera icon for the ''Eevee Not Bake'' collection on the outliner.

Make sure to save the file, the lighting data gets saved when you save the file.

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To render in Cycles:

Turn off the screen and camera icon for the ''Sun'' object in the outliner.

Change render engine from Eevee to Cycles.

Scroll down to Color management in the render properties: Set the look to High Contrast.

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The interior is darker than the exterior: For interior renders: just increase the Exposure in the render properties on the right.