Since the IKEA store opened to great fanfare in March, it’s stood alone in the 93-acre Riverpoint Marketplace. But now Wal-Mart has begun construction on a supercenter that will sell groceries. Also, Home Depot is locking up a site and hopes to have a new store open before the end of next year. Negotiations are also underway with Applebee’s, In-N-Out-Burger, and Taco Bell. Riverpoint Marketplace stands to be West Sacramento’s largest source of local tax dollars, generating three and a half million dollars each year when it’s built out.