I own a warehouse of 73,000 square feet. I have a single tenant currently in the whole building. They want to downsize when their lease is up in a few months. They would still be in most of the building. They estimated the space they want to keep at 61,600 square feet. We had our architect measure it and it was actually 56,683 square feet. We have an amendment they are ready to sign to take 61,600 at our agreed rent of $6.95/sf. Do we need to tell them that the space is actually less square feet. If we do, they will expect to pay less rent. The lease just says the space is approximately 61,600 sf. The tenant is not a Jewish company. Thank you.
It is not tous akum-because you are asking him to pay more than he agreed to. If they are paying per square foot you can’t charge for 61,600 sq ft when they are getting 56,683. The source is siman 348 seif 2 where there is a machlokes whether a person is allowed to cause a gentile to make a mistake and the second opinion which according to Shach 3 is the authoritative opinion is forbidden and even according to the lenient first opinion it would be prohibited bec. one day the gentile renter may measure himself and realized you were dishonest.
Answer is from Horav Fleishman shlit”a