i agree with Nanay on this. Cockatiels can be amazing compainion birds- mine is, she is so loving and gentle and quirky! but the dander is annoying. I have allergies to everything under the sun- cats, dogs, trees, grass, dust, pollen, scented lotion...you get the point. and in my previous apartment the cockatiel dander wasa little bothersome for me. i had carpet there, and i had to vacuum constantly or i would get sneezy. however, now i have the same bird in a room with wood floors, and much less of a problem. from my experiance at least i think so long as you keep their area clean, and they bathe regularly, it shouldn't be an issue - i bought a hepa filter and that made it pretty much unnoticable to me. and its kind of cute when they shake their feathers out and make a little puff of dust...
Do you plan on keeping him in your bedroom? this might be a problem if you have allergies, but if you have a room with good air circulation that you do not sleep in to keep him in, it isn't likely to bother you.
Also, Wednesday is far cleaner than my budgie when it comes to eating and throwing things and etc, and her poop is really easy to clean up, just like myartha said it is like budgie poop but a bit bigger. (in fact when i first got zoot, who wasn't my first budgie, but the first one i had had in a long time, i saw his droppings and exclaimed to my now ex boyfriend - "aww! even his poops are cute- their little versions of wednesdays!"-- for some reason the bf wasn't as interested in this as i was)
this post was long, and really just repeating what other people said. i just wanted another chance to declare my cockatiel love.
also, that cockatiel would benifit from living with YOU, I know how you spoil Levi!
I have a little problem with looking at the ads when i shouldn't, too. I just had to talk myself out of adopting a linnie yesterday, and one that was bonded to a little budgie- all that time i was seriously getting ready for one, and had spoken to a breeder, but was going to have to have one shipped to me, because i couldn't find any locally- and now there is one a few towns over! but, i have to remind myself that i signed a lease saying there will be no more pets than the 2 birds i moved into the apartment with, and also i have to remind myself that my roommates probably already think i am a crazy bird lady, if i went from 2 birds to 4 all of the sudden, it might not be so great for those roommates...sigh...someday i will live in an apartment with only other bird lovers...