Take note of everything in the kit and buy separately.
Once I made a list what you need to start homebrewing:
1) Boiling pot (usually not provided in kits)
2) Wort Chiller (very nice to have not provided in kits)
4) Fermenter with air lock (plastic bucket with lid is fine)
5) bottling bucket
6) tubing and bottle filler wand.
7) bottles (does not come with kits)
bottle caper (bench model is nice)
9) bottle caps
10) cleaner and sanitizer (not in kits) like OxiClean/PBW and StarSan