Estimate the miles and pay both ways. Give a check to the process server. Other proof may take the form of documents. Bring a copy of any contract at issue. Bring estimates, letters, bills or other relevant papers.
Pictures sometimes make powerful evidence.
A statement, estimate or testimony from an expert can be particularly helpful. A mechanic, a repairperson, carpenter, doctor, real estate agent, etc., backing up your story can make a large difference. You should also decide in advance if you wan to have a court reporter present in court. If there is a chance that you may appeal the case, you probably will not win without a transcript. If you learn that you cannot attend the hearing, request a continuance as far in advance as possible.