Another problem with people living closer together is noise disturbance. 

You could also suggest your tenants call child protective services if there is no supervision for young children and call the police for late night noise disturbances.

Stop giving warnings and start taking action.When someone disturbs the neighbors, I give them a written warning that it is unacceptable behavior.

The work will take place during the day, so it shouldn't disturb their nights.

Some are specifically marked "occupied do not disturb occupant" so you can't go in those.

I see it as a liability and could disturb current tenants.

It depends on how frequent this is, and the level of disturbance that it's causing to other tenants or neighbors.

After many attempts to go to the HOA and property management company, they say there is nothing they can do, they have tried warning him, etc (The HOA rules and regs mention fines for noise disturbances, but I don't know if they have implemented that).

On a multi-family, I want it cleaned immediately before it disturbs the neighbors.

Some have no IDEA>>>Give her instructions to text you with repairs so you have a record of her request or to email them.Give her instructions she is not to disturb other tenants,,"re dog poop" that you've had a complaint and if she continues to disturb other tenants you'll take action...