I use 3D Home from Broderbund, about $10 at Walmart or slightly more for the current version. It has some drawbacks but is easy to learn and the symbol library is not too bad. It covers the basics. It will not do for a lighting layout or to render lighting.
I use Autocad LT to do layouts where I need to see the joists or ceiling grids to layout fixtures. This takes longer to learn and is about $800. It will not do 3D, only the full version does that, but it is over $3000.
Email me with any other questions or I can call you. Send an email with your number and best time to contact.
