Congrats on the apartment!
I have lived in two apartments with my dog Ash. She's a medium size breed (Australian Cattle Dog), weighs about 40 lbs and comes up to about my knees. The first apartment we had was on a corner too, which helped a lot. She did bark and growl, but not too much and quickly got used to it. My second and current apartment is upstairs and it's even better. I would normally never want to be upstairs just because of how much more difficult it is to move in or out, but with a dog, it works out very well. Since we're upstairs AND on the corner, it's less noisy.
Ash is a herding dog and most people told me that it wouldn't work having that kind of dog in an apartment, but it does work. I exercise her and when I leave her alone, she's tired and has a kong filled with either her breakfast or dinner. She sleeps most of the time. I also leave the tv on and keep all the blinds shut (even though she can't really see people outside since we're upstairs). She barked a lot at first, but she's fine now and I think she just sleeps. I crate her when I leave her too so she's not just wandering around. I may start letting her free roam, but I feel more secure with her being in the crate for the time being.
My biggest problem with apartment/dog living is when I have to take Ash out to the bathroom. Ash HATES strangers and so I have to look out of the window first to make sure nobody is out there before I take her downstairs to the grass. If somebody comes along while I'm out there, it's just ugly and very irritating if Ash hasn't already gone.
I think as long as your dogs are tired and given toys that mentally and/or physically stimulate them, then you'll be fine. I have personally noticed though that smaller dogs tend to be louder. They bark more, but that's just in my experience. I'm not sure what other dogs you have besides the chihuahuas. A neighbor about 6 doors down from me has a dog that barks ALL day and ALL night. It's very frustrating. They leave it outside and in the small patio area and I feel horrible for the poor thing because they are located right next to one of the entrance gates. That dog can really hear everybody that comes and goes and it just must be so frustrating and scary for the dog. [
]