go to model info>statistics and choose purge unused. That dropped about 10mb. Your model is still poly heavy at over 6 million edges.
Choose low poly objects from the warehouse. You need to pay attention to the size of objects you are downloading and placing in your model or it will quickly become too fat to move. For example the table and chairs on the roof are only 373kb each, modeled with about 1000 polygons, not bad. But just downstairs the tables and chairs in the cafe are 7mb each, made with 71,587 polygons each, too fat.
if it’s too late to make different choices then assign the heavy stuff a tag that you can turn off while you work.
In SketchUp keep shadows and profiles off in your style, they take long to render.
Use low resolution imported images for artwork.
Assign all your plants from the front wall a separate tag, and keep visibility off until you are ready to output your layout images. That component alone is almost 2 million polygons.
In Layout turn auto rendering off and only render when you need to. Keep renders to raster, don’t render vector until the last moment if you need it as it takes much longer.