By Chris Dorrell Keir Starmer’s speech on Tuesday will have done little to dampen speculation about the potential tax rises in October’s Budget. The Prime Minister cautioned that Brits could expect a “painful” Budget, arguing the fiscal inheritance was “worse than we ever imagined”. Chancellor Rachel Reeves has already said that she thinks taxes will go up. In his speech today Starmer said that those with the “broadest shoulders should bear the heavier burden”. So where will Starmer and Reeves turn to raise some extra cash? Capital GainsMany in the City are nervous that Rachel Reeves is prepar…