Automatic Litterbox Central

So I have had my 2 cats for 4 years. When they were little, I experimented with the LitterSweep Ultra (piece of junk!) and toilet training (cats would rather poop on tables). So I have compromised with a normal litterbox - Booda Dome Clean Step (large litter area so few cleanings, steps reduce litter tracking, covered box reduces smell) and a durascoop (BEST SCOOP EVER).

But I moved into a smaller apartment, and the litterbox will be close to the kitchen. So I need the smells to be as close to eliminated as possible, and I don't want to scoop twice a day. So I caved and bought a Refurbished Grey Litter Robot II yesterday. When I get the box, I want to reduce smells and litter tracking as much as possible. I already plan on putting duct tape on the step to keep smells from leaking out of the drawer.

1. Should I buy the LR2 seals? Do they reduce smells, do they come with a base unit?
2. Does the lip extender and fence reduce tracking and or smells?
3. Anything else I should do to reduce smells?

Thanks!