Am i allowed to use names?

Any time you use an existing name be very careful. Contact the company or city and have them give you permission in writing. When you mention the names in your book, to you it may be innocent but the wording can be different to someone else and you could get a court fight. It may take a bit longer to get your book done but in a long run it could be worth it. There have been times I have read where the company name sounded like the real one but enough difference that it would be alright.