Teaching English overseas can be the perfect way to earn money for the experience of living in another culture.  For the most part, it's a great way to be paid for living an exciting adventure. However, what happens if you arrive in a country to teach English and within the first couple days your excitement turns to trepidation - the job adds extra hours, the apartment is far from the school, you have an unfavorable schedule with morning, afternoon, and evening classes spread out over the day, your employer demands that you work weekends, and the apartment isn't furnished? What do you do? Some teachers chalk these disappointments up to cultural differences and quietly endure the inconvenience to make the most out of a tolerable but certainly not expected or optimum situation.
Fortunately, you do not have to be this teacher.  As we'll see, most problems can be worked out to the benefit of all parties involved.

Hopefully, you have a contract. In most cases, even with informal hiring processes, there will be some sort of contract or agreement prior to arrival and this document can be your lifeline.  Refer to your contract politely but firmly and insist it be honored to the letter.  Next, keep your passport because it is even more of an asset to your independence and options.  Remember, only immigration authorities can hold your passport, and private employers may not. In South Korea I know teachers who forfeited their passport on arrival to their employer, and when the boss started docking pay on a policy not in the contract, they had no recourse. The situation deteriorated, the teachers quit, went to their consulates, and eventually were reissued new passports before heading to Japan. Some countries - Saudi Arabia for example - insist that immigration holds all passports, but this is the exception and not the rule. If an employer wants your passport then he or she really wants security and control because your passport is your ticket to autonomy. In South Korea my employer asked me for my passport but I told him that he did not have the authority.  This proved beneficial later when we had a few disagreements.

South Korea was the only country where I virtually signed on blind with a recruiter in Seoul. Though I started work questionably, my recruiter and boss assured me I'd have a visa soon. In short order I found myself overworked and uncertain. The contract stipulated a Monday through Friday schedule and thirty hours a week, but my employer insisted I work Saturdays, even though I already exceeded my thirty hours. Once I had my visa I stopped working Saturdays, and insisted that any work over thirty hours be compensated.

Many employers use the contract to get a visa, and will not abide by the letter of the law unless forced. My advice is to always keep a copy of the contract for referral. Hopefully you asked the proper questions before arriving (See Finding the Right English Teaching Job), and saved employer responses and printed all relevant email correspondence. In Argentina I was promised a furnished apartment, in Brazil I was promised Monday through Friday working from 1:30-6:30 in the afternoon, and in each case, when I complained about eventual discrepancies, having a hard copy of the contract and emails proved handy. In Brazil they needed me to teach in the morning, but compromised and allowed my day to be over at noon on Friday. In Argentina I ended up quitting.

Assume the best in your employer, as most are reasonable. In the United Arab Emirates I arrived to find the apartment did not have running water, and that my roommate and fellow teacher, rather than complain, took showers at the health club which flabbergasted me. This roommate had been deterred to inaction, in part, by a bad experience at the UAE driver's license bureau, and was so out of his proverbial element that I wondered why he had ever left home. I simply called my employer, explained the problem, and the situation was resolved immediately.

If you prefer to live by yourself then certainly request that you do so. A school saves money by housing teachers together, but they will usually work with you to find single living arrangements if you are willing to pay part of the rent. Once, in Korea, I knew someone who disliked his roommate so much for issues involved not passing important telephone messages, flushing the toilet, and taking out the trash that the relationship finally came to blows. One teacher came home to garbage dumped on his bed, and things spiraled further downward, leading to other's termination. They should have worked this out with the school, and I'm certain the employer would have tried to appease.

Quitting is a last resort. In the rare situation where the boss is simply offensive - whether racist, sexist or worse - the teacher may simply quit. I knew a Korean-American woman whose employers did not like the fact she was sufficiently "Korean" for their taste, and in Taiwan I worked with a colored South African woman whose boss was outwardly racist. In both cases the teachers quit and found better employers.
The only time I resigned myself was in Argentina. I was promised a furnished apartment, and what I received was a converted classroom. My kitchen overlooked another classroom, and only had a microwave and refrigerator. My employer had put a bed, desk, sofa, armoire and a couple chairs in an unused classroom and called it my home. On my first Monday I woke and a morning class was in progress, unbeknownst to me. I had to sneak with towel, passing the class, from my bedroom to the bathroom. I had arrived on a Friday evening and by that Monday I threatened to quit. According to my employer, a private apartment was too expensive, and the Argentine peso was valued such that he was having problems with expenses. We reached a compromise, but living at the school, where classes went from early morning to late evening, proved too much. As much as I liked the town and the students, I had to go, though I waited until school break and gave the school sufficient time to hire a substitute.

Be aware that your leverage relates to you being a valuable commodity as an English-speaking teacher. The foreign TESL teacher is difficult to replace, and you can use the fact to your advantage, but remember and be sensitive of the fact your coworkers are in a different situation, you probably earn twice as much as them, work less hours, and enjoy extra perks like an apartment. Most importantly, know that employers want you to enjoy your stay and will be genuinely concerned for your well-being. If you have a problem they will be more than happy to help.