I had this exact question recently. I just wanted a simple, 2D floor planner, for under £20. I purchased one from the Mac Store and it was so bad (no product measurements) that I asked for a refund. I then gave up.
Then LucidChart announced their new floor planner. It's great. Not a massive range of products, but it behaves very nicely. You can easily improvise products outside the range of chairs, sofas and tables with geometric shapes made to size - I just keep the Ikea catalogue open.
You can sign up for free and have up to 60 items; or pay a few quid a month for a subscription. It's a great program for flow charts.
Here's my plan, so far.
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