Just wanted to add a bit to the previous good advice.
I definitely support the suggestion to batch sparge. It makes things a bit more flexible, and you will be less reliant on a three-tier system. Having said that, a three-tier system is still pretty handy for batch sparging, but it will require three vessels.
I suggest going with two coolers (one 10 gallon for the mash and lauter tun, one 5 to 10 gallon for a hot liquor tank), and a turkey fryer. The nice thing about having the cooler HLT is that you only need one pot and burner (nice, if space is an issue). Otherwise, you will need two pots and you will probably want two burners (one to heat sparge water, one for heating the runnings). That all adds up to lots of space.
I use two 10 gallon coolers (see modifications in my sig) and a turkey fryer or pot on the stove:
The cooler set-up is really handy because you don't need a brew stand and you can pretty much move it anywhere. Plus the coolers can be used for other purposes, like chilling a corny keg full of beer, or as a cheap fermenation chamber (the 10 gal ones fit carboys really well).
And if you ever want to get into step mashing, an easy $35 add-on (steam injection system - see my sig for details) will allow you to heat your mash in the cooler MLT.
So, I highly advocate the 2 x cooler and 1 x pot/burner setup, especially if you are tight on space and need to be flexible on how/where you brew. Hope that is useful!