Honestly the best thing that you could do is ask your neighbours what their gardens are like or get some advice from a local landscape gardener. If you have a clay seam and or a high water table,you will need to lay land drainage, if its just the result of a wet winter, then adding gravel and spiking may be enough. If you are moving into a brand new house, I bet the builders skimmed off the topsoil and you will need to replace it, also the building activity will have compacted the ground and wrecked the natural drainage. What is your lawn for? Mine is pretty boggy at one end but is always green even in hot summers, but if you have kids, then it needs to be dryer and more hard wearing.