I think what he is looking for is the receipe for a saltwater tank. Sorry its a gaurded secret. No not really but everybody arrived at their tanks in different ways.
On the tank size I have to agree with what was said earlier, that bigger is better. It is more stable and forgiving. Also most people get a larger tank after a year or 2 anyway. (Why buy it twice) I am setting up a 210 up from the 55 and 75 I started with. Also get a smaller tank or plastic sump to put under the tank to hold the equipment.
For filtration there is the live rock and the skimmer.
As mentioned if you have the money buy it, otherwise use some base rock and seed with a few choice pieces. I made about 90% of my rock with concrete and used some live rock.
With a 210 in wall you will probably run a sump to hide the equipment. The skimmer can hide here also. You will find many a thread here about which skimmer to buy. Usualy the better ones cost a bit more. Euro Reef, AquaC ev240, Asm, Bubble king$ to name a few.
If you search 3 reef most people have talked about every skimmer out there.
You will need heaters. Always have a backup. Saltwater fish and corals cost a lot more then most fresh water stuff. Nothing is worse then getting home late and finding the heater is not working.
Lighting. One thing most 3reef ussers will agree on is that we all have changed our lighting at one point or another.
Since space is limiting you I would say use T5. They don't require a lot of space (less then any other option) but they will give you the ability to add on to vs. replace. If you start fish only and later start adding corals you can add extra ballasts and bulbs.
Now with this bit of information don't run out and buy everything but instead use the search function to find more detailed info about all these topics. Buy it right the first time and don't waste money.
Search: fuge, sump, skimmer, asm, bubbleking, euro reef, t5, ballasts t5, heater, diy rock, base rock, live rock, salt, saltwater books, tank build etc. Also most of the people that posted earlier have a build thread you can see the thought process in there builds. Take for example Otty, he has a great build thread for a 265g tank.
http://www.3reef.com/forums/show-off...iew-39314.html
Once you get the basic info ask a lot of questions and as Matt has said a thousand times "Take it slow"