Mostly echoing stuff that others have said upthread, but…
It appears that this community development organization does not have authority to issue a violation or collect a fine. They could notify the city, however, who does have the authority to do their own inspection and give you a notice of violation if warranted.
The trash cans are not a building code issue, but may still be a violation. Our city has a similar rule, although it’s not generally enforced. Generally (again, local ordinances vary) buildings are held to the building code in effect at the time the building was constructed. So your stairs may be OK based on that.
If it were me, I would ignore it unless I got a violation from the city. In the meantime, you may want to do some research on how the city deals with violations and fines just in case you do get one. There also may be an opportunity for appeal of the violation. In our city, they cite owners for fines a lot, but if the owner is cooperative, they usually waive the fine. The fine for them is more of a way to get the owner to take action immediately instead of putting it off. But all cities are different - you may want to go visit your local Building Department and get a feel for how vigilant they are about going after this type of stuff.
~Wednesday, board member of a city Construction Board of Appeals.