Saving 15% of your income for retirement is a worthy financial goal, but it's not easy to accomplish. The demands of day-to-day life can sometimes make saving any amount of money a challenge. Here are some ideas for making room in your budget to save enough without living like a monk.

Cut out fees

It's amazing how many low-fee or even no-fee options exist for a variety of products. Add up all the fees that you pay on a monthly or annual basis, then look at each one and ask yourself if there's a cheaper alternative. Don't forget things like fees on investment accounts and mutual funds; these charges usually come right out of your investment balances, so you may never realize how much you're paying.

You'll likely have to dig into your fund's prospectus to find out how much it's really charging in fees, but the effort is worth the potential savings. For example, if you have $10,000 invested in a mutual fund that's charging 3% in fees, you'll be paying $300 a year for the privilege of owning those shares. If the fund produces an average 7% return per year, then after 10 years you'll have paid $4,435 in base fees plus the lost returns on that money.

If you pay an annual fee on one of your credit cards, consider replacing it with a card that has no fee. If you really love your annual-fee credit card, call the customer service department and ask if they can waive your fee for the year. You'd be surprised how often credit card companies will be willing to do this, especially if you're a longtime customer.

If you manage to cut your various fees by just $200 per year and add that money to your retirement savings for the next 30 years, at a 7% rate of return, you'll end up with an extra $14,601.

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Negotiate discounts

Most people are used to negotiating on vehicle purchases, but they never think to try negotiating on other big-ticket items. But you really have nothing to lose by asking for a better price -- and you could gain quite a lot. So the next time you're in the market for a new appliance or a major repair, first find out how much this expense would cost on average (hint: Google is your friend), then use that number as a baseline. As a rule of thumb, aim for as much as a 20% discount on manufactured goods, a 30% discount on household items (including furniture and appliances), and a 40% discount on services. You may not always get that much of a discount, but these are excellent goals to keep in mind when negotiating.

To be a good negotiator, try the following tips. Always try to get the seller to name a price first -- that gives you a place to start. Your own first offer should be much lower than you actually intend to pay, to leave room for the salesperson to haggle your price up significantly. If the seller protests the price you offer or says he can't go any lower, look thoughtful and don't say anything. Most people find periods of silence uncomfortable, and the seller may be driven to say more than he should. Finally, and most importantly, always be ready to walk away from a negotiation. Worst-case scenario, you can always come back the next day and try again.

If you make one big-ticket purchase per year and save $700 on it by negotiating, after 30 years at a 7% rate of return you'll have an extra $51,103 in your retirement savings.

Make one-time payments on annual expenses

Big annual expenses, such as insurance premiums, can usually be paid either all at once or over several months. Most companies will give you a significant discount if you make the payment all at once. To make this easier on your budget, break out the payment into monthly amounts and save that much money each month in a special savings account. That way, you'll be sure to have enough to pay the whole sum.

For example, if your car insurance premium is $900 per year, you'd set aside $75 per month in a separate savings account. An account at an internet bank is a great option, because you'll earn a substantially higher rate of interest than you would in a standard bank savings account. When it's time to renew your insurance, you just transfer the $900 into your checking account to pay the bill, and you can take any extra money from the interest you earned and stuff it in your regular savings account to use for other expenses -- or save it toward the next year's bill.

Many insurance companies will offer a 10% (or more) discount for paying all at once, and some will throw in a small additional discount if you set up autopay with them. If you manage to save $250 per year using this approach, then after 30 years at that 7% rate of return you'll have an extra $18,251 in your retirement savings.

Getting the money to the right account

All of these money-saving approaches can be very helpful, but unless the money you save actually makes its way into your retirement accounts, they're not terribly effective. That's why it's important to "pay yourself first" and transfer money into your retirement savings account as soon as you get your hands on it. An automatic transfer can be an excellent way to guarantee that your contributions stay on track; 401(k) contributions are typically automated at a set percentage of your paycheck, and most IRA trustees will allow you to make automatic contributions from your checking account.

Having a well-funded savings account can help too, because it gives you another place to go when you need money in a crisis, aside from canceling your retirement account contributions. However nice it would be to have a little extra money now, it's even nicer to know that you'll have plenty of money around once you're ready to retire.

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