Add it to the monthly rent and "forget about it", as we Italians are famous for saying.You will never recover the cost to install separate water meters, a new water main to the building and the cost to install new water piping in the building to divide the piping to two systems.

Hi @Tal Hofman, generally speaking, they do not let you do that. 

This is why grant mentioned the tenants accepting a completely new lease with a new rent amount might work but definitely speak to an attorney first.

I will send you my email/phone number to speak more!

If you want to get fancy and complicated, speak with a REI attorney first (and probably a CPA). 

I would suggest speaking to a CPA before making any changes.

@Ihor KucheynykIt wouldn't hurt to shop, and I wouldn't mind speaking with you, but that is pretty solid in today's market.

I'd start here, as people with this designation frequently speak more than 1 language and specialize in working with clients from different countries around the world. 

Based on your COE (Certificate of Eligibility) you could qualify for basic plus bonus and that could be the ‘dream home' consideration (again, if there's a chance to move from in-laws yet to come) and speaking of for first time VA loan usage.2.)

I am speaking to quite a few HMLs for a new construction project.