Maybe I misunderstood, but it sounds like you actually intend to lay the cabling YOURSELF. I originally thought you said you were just going to plan what they needed. If this is a newly built house, planning the cable and recommending to them what they need compared to actually doing the cable job yourself are two very different things. For a new house, all cabling has to pass fire codes, building codes, inspections, etc. This isn't a simple matter of thinking you can do it. Alot of times for this type of thing most inspectors actually require the person to be certified for all the different codes, etc. I would definately seek the help of an electrician to actually lay the wires in the house.