Obviously you want the items you are buying you want to be genuine. Here are some tips to avoid buying fakes:

• if it sounds to good to be true, it probably is;
• look for sellers with a good rating who are local to where you are buying from;
• look for proof that the item is genuine i.e. photo proof or otherwise;
• find out the original source and research this to determine if it is plausible;
• look at the packaging and cross-check it to others using the Internet;
• see whether it is a reproduction as this will reduce the price; and
• determine if the item is a "re-issue" i.e. a collectible which has had a number of production runs over the years.

Most importantly, use your common sense!