For those just starting to invest, a mutual fund’s minimum investment requirement can be a difficult hurdle to clear. With some funds requiring initial investments of $3,000 or more, it can take months or longer just to invest in a single mutual fund. There are alternatives.

Three of the more common approaches are to buy shares of ETFs, find low minimum mutual funds, or use a robo advisor.

1. Buy ETF Shares

Here’s a tip I picked up from Matt Krantz of USA Today. Most mutual funds require a minimum initial investment. Even most Vanguard funds have a $3,000 minimum. When I started investing a long time ago, you could bypass the minimum investment requirement by agreeing to an automatic investment plan. Today, this option is often not available. So if you want to invest in a fund, but don’t have enough money to meet the initial investment requirement, turn to an online discount broker instead.

With discount brokers such as Scottrade, TradeKing, or OptionsXpress, you can invest in an Exchange Traded Fund (ETF) for about $5 a trade. For example, rather than buying Vanguard’s S&P 500 fund (VFINX), an investor could purchase shares of Vanguard’s Large-Cap ETF (VV). And while you do have to pay a few dollars for each trade, the cost is no more than an expensive cup of coffee at Starbucks, and the expense ratios of ETFs are generally lower than the cost of their mutual fund counterparts.

2. Find Mutual Funds with Low Minimum Investment Requirements

Schwab Mutual Funds: Schwab offers index funds with a $100 minimum investment.

TIAA-CREF: The minimum investment is $2,500. For those who sign up to automatically invest each month, the minimum drops to $100.

Dreyfus: As part of the Dreyfus Automatic Asset Builder, the minimum investment is $100 with automatic transfers from a bank account each month.

Nationwide Mutual Funds: The insurance company also manages mutual funds. These funds allow for no initial minimum investment as long as you signup for Nationwide’s Automatic Asset Accumulation plan and invest at least $50 a month.

T. Rowe Price: Its Automatic Asset Builder lets you invest for just $100 a month.

3. Consider Robo Advisors

There are several technology companies that have made investing both easy and inexpensive. These firms offer a diversified portfolio of low-cost funds with little to no minimum.

Betterment: Perhaps the best known, Betterment makes investing as simple as picking how much you want to be invested in stock ETFs and how much in Bond ETFs. From there, Betterment invests in about a dozen low-cost ETFs. They also rebalance and reinvest dividends automatically. There is no minimum investment or minimum balance required. You can see my review of Betterment or visit Betterment for more details.

Acorns: One of the newest and most interesting technology advisors, Acorns takes minimum investments to a new level. Once you sign up, it tracks purchases on your credit cards. It then rounds up the purchases to the nearest dollar. Once the balance reaches $5, Acorns transfers this amount from your linked checking account and invests the amount in a diversified portfolio of ETFs. You have significant control over the investment options, and the service is easy to use and reasonably priced.

Read more: Acorns App Review

Motif Investing: Finally, Motif offers diversified investing in stocks or ETFs with a minimum investment of just $250. It offers thousands of investment combinations. If you want to learn more about Motif Investing, listen to my interview with Tuhin Ghosh of Motif:

* Motif Investing has since closed and transferred existing accounts to Folio Financial.

Related: How to Invest with Little Money