I feel for you!
As a collage student we used to use the hall way in our appartment for a shooting range, couple yellow pages and some CB cap .22's we never missed at those close ranges and the noise wasnt bad if you used a long barreld 1950's era .22.
In door air rifle shooting is great as well, just crack a window open and run a fan if your worried about lead vapor.
You dont need wide open spaces to go shooting, when I lived in the city my friends used to go rat hunting with flashlights and air rifles in the industrial district at night. dodging the cops was 50% the fun.
back yard target shooting buy some them plastic animals and see if you can hit a 2" tall lion at 15' with your air rifle.
By some petstore mice & turn em loose in your living room and use your air gun you will learn to hit running targets fast.
BB abd CB .22's or air rifle in the back yard and shoot wafers off string, I found a 1980's era issue of American Rifleman that describes building a shooting box to help muffle gun shots in your back yard so as not to disturb your neighbors.
Air rifle is definately the way to go. if you have neighbors that plain dont understand and complain all the time if cannot see you or hear you they can't complain so erect some tarp coverd panels to block sight of the fun if they dont choose to partake in the fun, we used old office divider basses and some 1/2" conduit scavanged from a construction site dumpster and blue tarp and mechanics wire.
at 40yards Ive shot a chargeing bear target pulled by reved ATV in 3rd gear, nothing like shooting a moving target thats comeing at you at a fast rate!
I dont let my location deter me, I have a rubberband gun in my office, air rifle in my bed room, blow dart gun in the kitchen, sling shot in the garage, even a table top ropeing dummy so My family can team rope those table top steers, in the 1800's Folbert indoor firearms (parlor guns) were all the rage in Europe.
