I completely agree with Kim. Over the years we have applied for and received numerous trademarks including foreign ones.
This is an area that you must leave for the pros - that means not just using an attorney, but using a trademark attorney. Many times after you file an application with the USPTO, they will come back requesting modifications and changes. If you do not reply properly and within the required timeframe then you can really mess up or lose your application. Also there are many categories under which you can file for a trademark and you can get trademarks for the same service/product under numerous categories.
This is a very complicated area and it can cost you several thousand dollars to do it right. If you cannot afford to spend that money yet, then your business is not at the point where you should even be concerned about a trademark - it may be better to put that money into marketing and building your business.
BTW, if you are only offering your service/product within 1 state you can register with just that state, which is much cheaper. In fact, I believe that you need to operate in multi-state commerce to even be considered for a USPTO trademark.
Hope this helps - Jeff.
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