haha, nah you won't get scorpions in your apartment if you're in the city. If you are in the outskirts of the city, and near the desert, than you might get one or two but not many.
scorpions and tarantulas like the desert terrain, so they're hard to find in the city.
My friend's cat often eats scorpions (she lives out in the desert), and never gets sick or anything, so you don't have to worry about that. In fact, cats will make your home nearly scorpion free!
don't worry too much about scorpions. They are pretty slow moving, and easy to spot (as long as you don't have brown carpeting.) if you do happen to come across one, a shoe can kill it, but Raid is the best, because it's 99% effective.
The big scorpions look scary, but caution: BEWARE OF TINY SCORPIONS!!!! If you do happen to come across one, be careful, because they are more poisonous than the adult ones. Plus, baby scorpions are more likely to sting when they are frightened than adults. (But don't be too worried---like i said, you probably won't see many.)
As for tarantulas, they are nearly harmless, and only look scary. if you see one, you're lucky, because they are fairly rare in the city, and are almost never found in homes.
You only really need to worry about household pests, such as roaches and flies and such, because you'll be more likely to spot those than anything else.