Q: I have worked as a field sales representative for just under a year at this company. I was to be responsible for the wear and tear of my vehicle but to receive a gas allowance. If I achieved my sales quota, my base was to increase $500. The owner also expected me to use my own cellphone for business.

What has resulted is my driving 400 to 1,000 miles a week (I cover the northwestern states) and receiving a gas allowance that covers about a day's travel. After four months of driving, I had to replace my car, which I did because I had achieved every sales quota. I am the best salesman the company has. Despite this, the company owner went back on his promise to raise my base, and to worsen the matter, he lowered my commission, claiming he had to do that to help the company.

He led me on each month, saying that would be the month to make the change. All the while, the owner told me I was doing great. He finally agreed to raise my base, but not the commission. When I received my check, it didn't reflect the increase promised, and he has never paid me back commissions. I estimate that I make about $5 per hour. How do I collect the money I am owed?

A: You are probably not making $5 per hour, because you are responsible for the wear and tear on your new car, which you might not have needed had you gotten a sales job with a solid company that includes cars for its sales reps. Check with your state's labor department to file a complaint against your employer, but you must have written support to prove your claim. If your state does not have a government agency to represent you, consult an attorney concentrating in contract and employment law.

For any job paying commission, get a contract stating the terms. If you are considering a commissioned sales job for a privately owned company, never sign any contract until you have hired an attorney of your own choosing to review it. Any agreement is to protect both the employee and the employer and to explain the terms for all potential situations. Once you formally accept the job and sign the contract, keep a copy in a safe (fireproof) place. No terms can then be changed because of a private conversation with management. If the company won't put the change in writing, that shows you its value. Many privately owned businesses are highly reputable, but a contract or commitment letter is still necessary.

It sounds as if you are very good in sales but perhaps not so good in managing your business. It is a warning sign of what's to come if you can't get a term or condition in writing. If an employer violates a condition, consult an attorney immediately. Suing is not necessarily the answer and certainly would not come without a new set of problems, but there is no excuse for not knowing your legal rights and options. In all business environments, knowledge will help you make good decisions through your career.

If you needed the job to gain sales experience in the field, you have paid your dues and shown you can be successful. It's time to move on and find a job with an established company with a professional sales force. Keep your sales records to show your success when you interview, and don't share your emotions or negative thoughts about your previous employer. You are simply looking to move up.

Email your questions to workplace expert Lindsey Novak at [email protected], and follow her on Twitter @I_truly_care. To find out more about Lindsey Novak and to read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.