Residential group Grainger has agreed to buy a regional tenanted residential property portfolio from Sarunas Properties for £58m.The portfolio, which comprises 614 properties across Cambridgeshire, Greater Manchester, Lancashire, Cheshire, Derbyshire, Merseyside and Nottinghamshire, will bring the group's investment into residential assets over the last few months to £76m."It provides significant opportunities for value enhancement through a combination of refurbishment, active asset management and capital realisation, and is anticipated to deliver a double digit total return over the next five years," Grainger said in a statement on Monday."The remainder of the company's investment over the past few months has comprised smaller portfolio acquisitions across the UK, in line with Grainger's normal investment strategy."In total the recent acquisitions in the UK regions of circa £76m will generate nearly GBP6 million of additional gross rent for the company annually," it added, saying the price represents a discount to their vacant possession value of about £66m.On Monday, Grainger shares closed up 3.56% to 200.80p.