If you have been uncomfortable with your stock holdings on big down days like we've had recently, use Friday's strength to trim, said Jim Cramer on his "RealMoney" radio show.

Many mutual funds' fiscal years end in October, said Cramer, and many of those funds have been selling to lock in gains. But that selling is over as of Friday, he said, which is why the market lifted.

Cramer isn't looking to sell stocks here, but he knows many listeners "can't take the pain." For those who can't, use Friday's strength as an opportunity to sell, he said.

Be Skeptical

Recent stock market scandals such as Refco ( RFXCQ), Bayou Management and the late-day trading mutual fund scandal all have one thing in common, said Cramer: People don't like to 'fess up when they mess up.

It's really hard to make money in the market longer term, said Cramer. People mess up all the time. Sometimes they lie when they do.

So, be suspicious of routinely great performance with no turns, and make sure all the checks of that performance are in place. In each case of chicanery Cramer has seen, one or two, if not all, of the normal checks and balances were corroded, he said.

An investment manager should trade with a major brokerage that can't be bribed and should have a major law firm and an independent, outside accountant, he said.

Don't be had, Cramer added. Not accepting that people sometimes lie when they mess up and not looking for checks and balances in the system will cost you.

RealMoney.com contributor and "Stocks Under $10" co-author Will Gabrielski joined Cramer to talk about three stocks that tripped up Cramer in Thursday's "Stump Cramer" segment, during which callers ask about obscure stocks.

Gabrielski said Home Solutions of America ( HOM) had rallied about 250% this year as a play on the cleanup from the hurricanes. However, the company became public by means of a reverse merger, which means it bought a shell company to gain listing on an exchange rather than by going through the public offering process. Additionally, the company has sold stock to private investors at discounted prices, he said.Cramer said that kind of stock is "not my cup of tea," adding that he also doesn't like the brokerage companies that cover the stock. And, with the stock up 250% this year, most of the move has probably been made, he said.

Of HMS Holdings ( HMSY) and Fremont Michigan Insurance ( FMMH), Gabrielski said both stocks' trading volumes were too low to consider investing. Stocks with such low trading volumes are prone to manipulation and excessive volatility, he said.

A stock recently discussed in the Stocks Under $10 newsletter that Gabrielski likes is Hudson City Bancorp ( HCBK). Hudson City has 80 branches in the New York/New Jersey area, he said, and it is growing. Gabrielski believes the Federal Reserve will soon be finished raising interest rates, which will benefit bank stocks.

Cramer is not a fan of Toll Brothers ( TOL). He is especially worried about high-end housing as a result of speculation in that market. The only housing stock Cramer would embrace is St. Joe ( JOE) because it is a demographic play, he said.

In response to a question on Sears Holdings ( SHLD), Cramer said "I like it. I own it, and I keep quiet about it." Sears is a volatile stock, he said, and it is not for the squeamish. It's a special situation as Cramer believes his friend and Sears' controlling shareholder Eddie Lampert is doing a great job merging Sears and Kmart.

Cramer believes the easy money in Sears has been made and that the stock is now resting. It will take better earnings and more deals to get the stock moving again, he said. Cramer is not pounding the table to buy Sears because, with the economy slowing, now is not a great time for retail stocks. But, Cramer is patient and believes in the long-term outlook for Sears.

Cramer's favorite stocks now are UnitedHealth Group ( UNH) and Procter & Gamble ( PG).

Cramer would take the trade in Georgia Gulf ( GGC), he recommended recently.

Regarding Conexant ( CNXT), Cramer would sell a little and let the rest run, he said.

Lightning Round

Bullish

Cramer was bullish on Qualcomm ( QCOM), Inco ( N), Lexar Media ( LEXR), MetLife ( MET) and Prudential Financial ( PRU).

Bearish

Cramer was bearish on Bristol-Meyers Squibb ( BMY), Whiting Petroleum ( WLL) and Anheuser-Busch ( BUD).

At the time of publication, Cramer was long St. Joe, Procter & Gamble, Sears Holdings, Qualcomm and UnitedHealth Group.

James J. Cramer is a director and co-founder of TheStreet.com. He contributes daily market commentary for TheStreet.com's sites and serves as an adviser to the company's CEO. Outside contributing columnists for TheStreet.com and RealMoney.com, including Cramer, may, from time to time, write about stocks in which they have a position. In such cases, appropriate disclosure is made. To see his personal portfolio and find out what trades Cramer will make before he makes them, sign up for Action Alerts PLUS. While he cannot provide personalized investment advice or recommendations, he invites you to send comments on his column by clicking here. Listen to Cramer's RealMoney Radio show on your computer; just click here. Watch Cramer on "Mad Money" at 6 p.m. ET weeknights on CNBC. Click here to order Cramer's latest book, "Real Money: Sane Investing in an Insane World," click here to get his second book, "You Got Screwed!" and click here to order Cramer's autobiography, "Confessions of a Street Addict."

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