You are talking a lot of money. Moving the furnace will create a lot of problems. Its located in the center of your basement for a reason. Its so that all the heat vents will be balanced going to all the rooms. Changing the location of the furnace will change all that and will probably require re-doing a lot of duct-work, not to mention moving the gas feed line. Moving the water heater is not nearly as bad and will also require a new gas line. Changing the drain location on your floor may be the hardest of all. This will require a jack-hammer to break up your floor, re-lay the pipes and re-cementing. So as a professional who has finished many basements, i would recommend building a room around your furnace/water heater and design your basement around that. You need about two feet of walking room around the furnace/heater.