It really depends on your monthly income and the state of your buildings structure.

I gather that your building has no elevator. So the main emergencies you could have is the boiler and maybe some major plumbing work. Local Law 11 shouldn't apply for your building ( facade maintenance )

Typically banks require that coops maintain at least 10% in reserves, which is by far not enough.

You should have enough money in your reserves to cover emergencies like replacing a boiler if it's reaching it's life expectancy for example. The roof and facade should be on your list as well.