The best stocks for your retirement portfolio aren't always trading at reasonable prices. Sometimes, it's worth waiting for a better price before buying into a great income stock.

We asked a panel of our top investors to share some tickers that retirees might want to keep on their watch lists for a pricing pullback. These are great stocks for any retirement portfolio, just not at today's overheated prices.

Read on to see why they recommend AvalonBay Communities (NYSE:AVB)Taiwan Semiconductor Manufacturing (NYSE:TSM), and Welltower (NYSE:WELL) -- just not at their current prices.

A woman stacking coins in piles of increasing height.

Image source: Getty Images.

An excellent company for a not-so-great price

Matt DiLallo (Welltower): Healthcare property-focused real estate investment trust Welltower is a good option for retirees. Thanks to the steady rents collected from its portfolio of predominantly senior housing properties, the company offers retirees an attractive current yield of 4.7%. Also, that payout is well supported since it only consumes 82% of the company's cash flow while its investment-grade balance sheet and improving credit metrics provide further support. Add to that the fact that demand for senior housing should continue to grow at a healthy clip given the aging of baby boomers, Welltower's strategic position should deliver steady dividend growth.

That said, the company's top-notch financial profile and growth prospects also come with a premium price tag. At its recent stock price of $75 per share, the company trades at nearly 18 times the midpoint of its funds from operations (FFO) guidance. While this year's earnings are currently under pressure after the company sold several billion dollars of assets to reposition its portfolio for the future, its valuation is still well above that of others focused on healthcare real estate.

For comparison's sake, hospital-focused REIT Medical Properties Trust (NYSE:MPW) currently trades at 10.2 times projected 2017 FFO and 9.2 times next year's earnings. Because of its lower valuation, Medical Properties Trust offers retirees a much higher current yield of 7.2% despite offering a similarly strong financial and growth profile.

Given Welltower's valuation, retirees might want to put this stock on their watch list and wait for a pullback. That could enable them to not only get a lower starting price but also lock in a higher yield, which has the potential to drive higher total returns over the long term.

Home is where the investment is

Sean Williams (AvalonBay Communities): One company that's been red-hot of late but that could be a perfect stock for retirees to target on a substantial stock market pullback is apartment-based REIT AvalonBay Communities.

Generally, a rising interest rate environment is bad news for apartment-based REITs for two reasons. One, they tend to borrow money or issue stock in order to fund new construction or apartment community acquisitions. This makes borrowing more expensive when the Fed is tightening monetary policy. The other issue is higher interest rates usually boost the yields of interest-bearing assets like CDs and bonds, making dividend-paying REITs appear riskier.

However, AvalonBay isn't your typical apartment REIT. Its focus is on a more affluent clientele, which lends to some serious advantages. Namely, when there are hiccups in the U.S. economy, its renters are far less likely to be adversely impacted than lower-income renters. The fact that AvalonBay targets a middle- to upper-income clientele means it has excellent occupancy rates, and it's able to pass along rental increases that easily surpass the national rate of inflation.

AvalonBay's portfolio is also well diversified, with its second-quarter financial results showing that it generated 20.8% of its net operating income from Southern California, 20.5% from Northern California, and 23.7% from the metro New York and New Jersey area. It tends to focus its efforts on areas of rapid real estate growth, but it's doing so with success on both the East and West Coasts.

Lastly, consider the positive impact that higher interest rates could actually have on AvalonBay's bottom line. Monetary tightening would be expected to increase mortgage APRs, potentially pushing prospective homebuyers back into renting. This is only going to give AvalonBay more rental pricing power.

Currently sporting a 3% yield, this REIT should most definitely be on the radar of retirees during the next stock market correction.

Close-up shot of a circuit board, populated with microchips and other components.

Image source: Getty Images.

A terrific income tip from Taiwan

Anders Bylund (Taiwan Semiconductor Manufacturing): Microchip builder Taiwan Semiconductor, or TSMC for short, is a fantastic long-term investment on its own merits. Over the last four quarters, the company generated $4.7 billion of free cash flows out of $31 billion in top-line revenue, and returned all of that cash to shareholders in the form of dividends.

Amid rising demand for semiconductor manufacturing services, TSMC's annual revenues have increased by 63% in the last five years. Dividend payments more than doubled over the same period.

TSMC is a little unusual because it doesn't send out dividend checks on a quarterly basis. Instead, it issues dividend payments once a year, typically in June or July. That doesn't change the value of TSMC's dividend policy, but it's something investors should be aware of. Don't expect a steady stream of smaller dividend payouts -- there's a larger lump sum headed your way next summer instead. The meaty yield of 3.1% can certainly power your retirement portfolio with large, lumpy dividend checks.

However, the stock -- or technically, the American depositary receipt with each stub representing five TSMC shares on the Taiwan stock exchange -- has gained a market-beating 30% so far in 2007. Trading at nearly six times trailing sales and 17 times earnings, the ticker is running a little hot.

In the words of master investor Warren Buffett, "It is far better to buy a wonderful business at a fair price than a fair business at a wonderful price." TSMC is a wonderful business. Today's share prices might not qualify as "fair." You could buy this stock today but it's probably a good idea to wait for a pullback before jumping in.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.