Depends on your experience. I built a Big Sitk 60 from scratch in about 5 nights working 3 to 4 hours a night and one weekend. Depends on how fast you build. Kits can be pretty quick. I can put a wing together in an evening on most sport type planes, and the fuse and tail surfaces in another. Sanding and getting things prepped usually takes another, sometimes 2 if it is a really rounded fuse. Covering takes the longest, and then the radio install takes a full night usually.

Depends on how fast you build and how long you have to spend in the instructions.