Toward the end of the year, you may be putting your extra cash into holiday gifts. But it's also a good idea to offer yourself something. I'm talking about the possibility of future wealth. And that's by investing in companies with solid long-term prospects. Why buy now? Because so many of these top stocks are trading at dirt cheap valuations.

You can start investing -- or add to your current portfolio -- with any amount of money. But here I'll talk about investing $500. With this amount, you can get in on all three of the following stories, or make a bigger investment in just one. Let's take a look at three stocks to buy before you ring in the new year.

1. Disney

Disney (DIS 0.34%) is heading for a 35% decline this year. So, share performance clearly hasn't been anything to cheer about. What are investors' concerns? Costs. Disney has been struggling with higher costs in various areas of its business. This has weighed on earnings and on demand for the stock.

But Disney may be at a positive turning point right now. First, in just a couple of days, the company will start charging more for its streaming services. Increases apply to Disney+, Hulu, and ESPN+. For example, if you want to continue watching Disney+ without ads, you'll pay $3 more a month.

Second, Disney is setting off on a new path to boost growth, with longtime CEO Bob Iger back in the driver's seat. Iger agreed to come back for two years and then name a successor. During his tenure, he grew earnings at Disney and was behind key acquisitions, like Pixar. So he's an ideal person to lead Disney right now.

Even before Iger's return, Disney already was showing strength in a key area. Its parks, experiences, and products business grew revenue 73% in the recently ended fiscal year. Demand has been strong at the company's theme parks. And, historically, this part of the business has been the biggest moneymaker.

Today, Disney shares trade for 23 times forward-earnings estimates. That's about half the level of earlier this year. Considering momentum in the parks business and Iger's return, investors may have a lot to gain by getting in on this story as soon as possible.

2. Target

Higher inflation is weighing on Target's (TGT 0.59%) margins -- and on its customers' wallets too. The company's recent earnings came in below its own expectations. Target noted that shoppers are focusing on buying essentials, and across any product category they're looking for bargains.

So why should we run out to buy this stock? Today's economic situation is tough. But it's important to keep in mind that it's temporary. Target has the strength to weather the storm and thrive once the situation improves.

Even in today's difficult environment, Target managed to increase traffic and basket size in the third quarter. This was the company's 22nd straight quarter of comparable-sales growth. Target also made market-share gains across its merchandising categories. All of these points are important because they show customers keep coming back to Target.

At the same time, Target is putting into place a plan to increase efficiencies. And it expects this to save $2 billion to $3 billion over the coming three years. Target also continues to remodel stores, improve same-day fulfillment capacity in certain locations, and open new stores.

Target shares are trading for 29 times forward-earnings estimates. That's down from more than 40 earlier in the year. Today's level looks pretty reasonable if we consider Target's track record of growth, resilience today, and future prospects.

3. Abbott Laboratories

Abbott Laboratories (ABT 2.48%) has four businesses: medical devices, diagnostics, nutrition, and established pharmaceuticals. Traditionally, medical devices has been the biggest contributor to revenue. But in recent times, Abbott's COVID-19 testing business pushed diagnostics ahead.

Should we worry if coronavirus testing falls? No. Even if one business area weakens, Abbott's other businesses offer enough strength to keep growth going. One of Abbott's biggest products is the FreeStyle Libre continuous-glucose monitor. It brought in $1 billion in sales in the quarter. And the company continues to win new product approvals to drive future growth.

Abbott reported global sales of more than $10 billion in the third quarter. And the company increased full-year earnings-per-share guidance.

You'll also like Abbott for its dividend growth. The company is a Dividend King. That means it's increased its dividend for at least 50 straight years. So even during tough years like this one, you can count on income from your investment.

Why buy now? The stock looks cheap, trading at 20 times forward-earnings estimates. That's down from more than 27 earlier this year. So, investors who add Abbott before 2023 are getting a great price on a stock that will bring them passive income -- and possibly great gains over time.