Martinsa-Fadesa SA, the largest Spanish developer with a residential project in Sofia, has sought bankruptcy protection, Bloomberg agency reported as quoted by website investor.bg.With the 10-year real estate boom in Spain beginning to die down, more companies fail to secure a loan for refinancing old debts. What makes it harder for developers to pay their debts is the sharp decrease in home sales in addition to rising borrowing costs, the agency said.Martinsa has a total of 5.2 billion euro in debt, which accounts to investments in houses, holiday resorts, golf courses and shopping malls. At the end of June, the company's assets were valued at 10.8 billion euro, down from 13 billion a year ago, Bloomberg reported.The Spanish developer failed to obtain 150 million euro loan with which to finance ongoing construction projects. Martinsa now intends to raise money through selling some of its property and land management.In Bulgaria, the company is represented by Fadesa Bulgaria, which oversees the construction of Modera Residence, located in the Sofia borough of Vitosha.As previously reported by The Sofia Echo, the construction of the complex began on March 18. It is featured on a land plot of 14 000 sq m, and the architectural plan envisions three residential blocks with a total of 335 flats, connected to row-rise retail building.A 7000 sq m shopping zone within the complex is also planned, as the public and service area will include a supermarket, a kindergarten, a few catering facilities and 36 shops. According to initially announced deadlines, the complex should be completed by March 2010.