I am sorry to be the one who puts forward the 'bad' news but:
It takes a lot more than live rorck and live sand for a successful tank. I am not claiming to be an experienced hobbyist but i have kept saltwater tanks for ten years or so.
My best advice is that you should invest in agood recently published book before investing in a tank. Then you will be able to determine what you need, how to set it up, and probably what are the costs involved. This hobby is expensive,
However, I can suggest some necessary things for a fish only tank:
Live rock, sand bed, powerheads, protein skimmer, lights, heaters, test kits.
You also need a quarantine tank (lr, ls not needed for this tank) with some type of filtration.
Buckets for mixing and keeping freshly made saltwater for changes (you will have to have a heater and a powerhead for this purpose)
You really need a source of reverse osmosis water (either a unit so you can make it, or a supllyer where you can buy it)
And my advise: There is no way to cut corners in saltwater tanks. You must do it right from day one, or you will up paying the price at some point (I am speaking from experience here)
If you do it right in your first try, this is a very rewarding hobby, and your family will spend hours of enjoyment. If you mess up, you will end up searching for ways to get rid of it.
There are people that get by without q tanks, without ro water, however, I have not met one of them yet. I only read about it in message boards.....
I am really sorry if I disapointed you but you will read, hear or realize the necessity of the time and money involved here.....