The reason is very simple that big builder will have big margin and this is only posssible where builders construct premium houses or builders plans to construct affordable houses with a very low inverstments which is not possible in Raj Nagar Extension. Ghaziabad area have a good demand for affordable houses, investors wants premium housing where as end users want affordable housing. Due to low demand for the premiun houssing big builders stay away. Moreover the builders have to buy lands directly from the farmers which is always costlier.