In my opinion this will make a good online furniture store. Its long but still it sounds good to me. Its better if you develop it. For now lets say a value of some $xxx. Good luck with it.
The niche is good. However, adjectives added to the name have a tendency to greatly hurt their value. Not only because it turns out to be a longer domain, but because it's not as unique as the ones you found at Namebio. Instead of "great", one could use "good", "super", "prime", "excellent", and so on. I would say low to mid $xx.
i don't think using those prefixes as a replacement, would enhance value for that name either.
some ideas that probably are taken would be:
"barginfurniturestore or customfurniturestore or antiquefurniturestore or discountfurniturestore or even giantfurniturestore.