I've been teaching overseas for over ten years, mostly in Asia. While I don't have any experience in eastern Europe, I believe conditions are fairly similar. I think it's important to note that there really are not any standards, but what I would classify "good jobs" and "not so good jobs". I'll discuss the good jobs.
1. Out of the many jobs I've had, most have paid for airfare. For a few jobs, I had to wait a certain amount of time before I would get reimbursed, such as at the end of the contract. If the employer is willing to pay for airfare at all, it is probably a decent company/school.
2. Some employers will set you up with accommodation, while others will help you look for a place to live. In Japan, most employers will give a housing allowance of around 10,000 yen. In China, I had housing provided at no cost. On the other hand, in Thailand, housing is at the expense of the individual. So, this question really depends on the country where you are going.
3. I've had a health insurance plan at every job. Most health insurance plans do not include travel insurance, so you are not covered when you leave the country where you are living.
These are all important points to consider, but also ask questions about the actual job. It's good to know how many hours you will be required to teach, and if those hours are in 8-hour blocks.
Best of luck!