Most personal finance experts would recommend paying no more than 30 percent of gross (before tax) monthly income for rent. Another target is to spend no more than 50 percent of net income (after taxes) on rent, utilities and all other monthly living expenses. However, there is no one-size-fits-all model, and the best way to decide is to write out exactly how much you earn each month, how much you spend on living expenses and how much you want to save. Then tailor your budget accordingly.

The 50-20-30 rule is a recommendation for how to spend percentages of your after-tax income on specific expenses. According to this rule, you should put 50 percent towards "needs" (rent, bills, groceries and the like), 20 percent towards savings and 30 percent towards "wants," like shopping, hobbies, traveling and going out to eat. Read this article to learn more about percentages of income and rent.

On $50,000 a year, you’re making $4,167 gross per month. Taking 30 percent of that, you should be able to afford up to $1,250 per month in rent.

On $100,000 a year, you’re making $8,333 gross per month. Taking 30 percent of that, you should be able to afford up to $2,500 per month in rent.

You should use net income. Gross income is much easier to calculate, but because tax rates can vary by state, city, income level, family size and many other factors, your net income is a more accurate assessment of what you can afford.

No, but not making that much can be an issue. Many landlords require you to make at least that and may turn you down if you don’t. You’re also likely to face financial hardship if your rent costs more than that, so most experts would recommend it, even if it isn’t an absolute requirement.

Most experts — and the federal government — recommend that you shouldn’t spend more than 30 percent of your gross monthly income on rent. Your total living expenses (rent, utilities, groceries and other essentials) should be less than 50 percent of your net monthly household income.

If you’re trying to save up and don’t know exactly how much rent will be, take out 30 percent of your paycheck. If you do know, take out the appropriate amount from each paycheck. For example, if you’re paid every two weeks, take half of your monthly rent payment out of every paycheck.

Take a look at your bills for the past three months and determine what the average was. Do this for each of your bills for electricity, gas, water, internet, cell phone and anything else you might have. Take the average total cost of these expenses, divide it by the number of paychecks you receive per month and then set that amount aside every time you are paid. For example, if the average cost of all your utilities for the past three months was $300 and you receive two paychecks per month, put $150 aside at every paycheck. If you don’t already have utilities set up, ask your neighbors or landlord for an estimate of what’s normal.

To determine your monthly rent budget, estimate no more than 30 percent of your gross monthly income on rent, assume one month’s rent for a security deposit, add another $200 to cover utilities and then throw in additional necessary expenses and hidden costs such as pet fees, parking and laundry. Try to keep these costs below 50 percent of your total net (after taxes) income.

A 50-50 split sounds fair, but it’s not always right for everyone. If one of you has a significantly larger bedroom or better access to apartment features, such as an attached bathroom, it may make sense for that roommate to pay a slightly higher proportion. Whatever you decide, the most important step is to discuss it before you move in together and document your decision in a roommate agreement that will prevent this from becoming a bigger issue down the line.