How much would it cost for a new kitchen, bathroom, and boiler?

This question is almost impossible to answer, it depends on which appliances, what design kitchen units, what size an type of boiler,what design bath suite, how much piping is needed, proximity of existing pipe work to new boiler position. All these points and more are variable costs, and impossible to estimate without seeing and measuring the rooms, things like door and cupboard position have to be taken into consideration, whether the floors are wooden or concrete or composite board. You would be better off getting someone to measure up, and quote you from the measurements.