Grainger, the FTSE 250 residential property firm, has agreed two new debt facilities.£840m will be provided by five major banks in what's called a Forward Start Facility, with another £50m raised with a firm called Partnership Assurance.The refinancing means Grainger's average cost of debt will be 5.8% with average maturity at 5.9 years.Grainger's finance director Mark Greenwood said of the deals:"These transactions give Grainger far greater certainty over its medium and long term financing and are in line with our stated financing strategy."Grainger shares were up 6.8% in early trading.BS