Biggest challenge was learning to cut quilting squares..had no idea..But I bought a Tailor cutting ruller and a cutter, watched a few videos on you tube and went to town..
With cutting and assembly the time was approximately 4 hours for the large tree, 2.5 for the middle size and about 1.5 for the small one..
Be prepared for breakdowns with a comprehensive service contract for your Subaru. Warranty plans are available for all Subaru models including the Impreza.