Shares of apartment owner Post Properties ( PPS) surged 18% after the company said it received a buyout bid from its former chairman and a Canadian pension fund. Post Properties, which owns 62 apartment properties across Texas and the Southeast U.S., has been the subject of buyout speculation for over a year now. On Wednesday, the firm said it received a proposal to be acquired at $44 to $47 per share in cash. The bidders are Cadim, a division of Caisse de depot et placement due Quebec, and Williams Realty, which is controlled by Post's former chairman John Williams. The buyout offer is not subject to financing conditions, Post said. In response to the bid, the company has begun a formal process to seek proposals from other potential buyers. Post Properties shares were climbing 18% to $42.18 in afternoon trading, and the news lifted other apartment REITs as well. BRE Properties ( BRE) surged 9% to $41.68, AvalonBay ( AVB) rose 7.5% to $92.85 and Equity Residential ( EQR) climbed 6.5% to $36.12. The bid could be just what REITs need to get going again. After sharply underperforming the S&P 500 last year, REITs are now outperforming this year -- although the sector is still down. The U.S. MSCI REIT Index has lost about 8% year to date through Tuesday, while the S&P 500 has fallen about 11%. On Wednesday, the REIT Index rose 4%, while the S&P 500 fell 1.7%. Dean Frankel, portfolio manager with Urdang Investment, says that apartment stocks are trading at very sharp discounts to net asset value, or the price at which the properties would fetch on the private market. Frankel said the Post Properties bid may get investors to start focusing again on net asset values among REIT stocks. "Maybe people will not be so willing to short these things anymore," Frankel says. Frankel says that apartment owners may face tougher fundamentals given the slowing economy, but stressed that valuations are particularly attractive in the group. Urdang, which is a dedicated real estate fund, is overweight the apartment sector, he says. Frankel says BRE Properties is a good play on the sector, noting that the stock is at about a 40% discount to where its assets would trade in the private real estate market. He grants that the apartment stocks may not go back to trading at NAV and may instead remain at a 20% discount. Still, that implies about 20% of possible upside in BRE's stock right now. Urdang owns shares in BRE.