Based on the benchmarks for Total War Rome 2 in the link below, the game is actually a bit demanding if you want 30 FPS with the lowest settings. Note that results are average FPS, not minimum FPS. So if "solid 30 FPS" means a minimum of 30 FPS, then I recommend looking at dedicated graphic chips / integrated graphics cores that can provide an average of 40 FPS just to be sure. In short, a £100-150 laptop will not be good enough to play the game. It will be difficult to even find a used laptop within the range that is capable of playing the game with "solid 30 FPS". You need a laptop with either an Intel HD 4400, Radeon HD 8550G or the Radeon HD 7610M. Ignore the Radeon HD 8470D because that is only found in desktop AMD APUs...