Many landlords have to deal with loud tenants (not to mention the neighbor's complaints of excessive noise). It's so common, that I bet you've faced the same issue in your rentals at least once during your landlording career.
Here are a few tips on how to deal with noise in the rental without losing a good but noisy renter:
Establish a quiet hours policy.
A quiet hours policy is often associated with college campuses, and states that students aren't allowed to make too much noise at certain hours. Many landlords choose to carry that policy over to the individuals who live in multi-family buildings in order to help keep the peace.
Spending time in a quiet and pleasant atmosphere after a stressful (and sometimes noisy) day at work is essential for everyone. So a quiet hours policy included in the lease agreement might be a great solution to avoid possible neighbors' complaints of excessive ongoing noise at midnight and reduce noise level in the rental.
First determine the hours during the weekdays as well as weekends, when the noise that might disturb others isn't acceptable (for example, from 10 p.m. to 8 a.m. on weekdays and from 11 p.m. to 9 a.m. on weekends), explain on what occasions the policy is violated and outline penalties for non-compliance with the noise clauses. Also, take into account specific local laws and regulations in your area.
Investigate the neighbors' complaints.
For landlords, it's not easy to monitor what's going on in their rental properties. But no worries! The neighbors will probably let you know if they happen to hear any unreasonably loud noise coming from your rental.
Keep in mind that not all the complaints from the neighbors are valid. As you're partially liable for your tenant's actions, investigate the matter before requiring a fine or evicting a tenant. Some people are just too sensitive to noise or tend to dramatize things.
Soundproof your rental.
Proper interior and exterior soundproofing helps to eliminate the noise. Exterior soundproofing, like fixing the gaps around your doors and windows, is a quick way to immediately reduce sound leakage.
If the problem stems from interior problems (i.e. loud footsteps or music) provide a thick rug pad for your tenants and hang acoustic panels to reduce unwanted noise. In the past, I've even let tenants pick out a new rug to put in the space. Reduced noise complaints were worth the extra hundred dollars I spent. You can also give your tenants furniture pads if the noise issues come from furniture. Bonus: they help protect your floors. There are numerous types of acoustic insulation, so just choose the one that suits your needs.
Consider tenant screening before signing a lease agreement.
To ensure that you're dealing with a good tenant who won't breach any of the lease clauses, run a background check on them. If you have a thorough tenant screening report, you'll find out if there were any issues regarding violating a quiet hours policy or any legal complaints from the previous landlords.