I typed the search term Toowoomba Building and Pest Inspections into Google just to see what sort of search results Google Places would provide when using an address that contains a letter – like 220B. I feel that Google gets a little lost when providing these sorts of results which is a little disappointing, especially if you are a business owner with a letter atached to your address. See example below:

You can see by the Google search result that the Google Places has placed a makr on the map where the business is but it has not allocated a letter. I dare say that this would be different if the business owner had an address without a letter within it.