Legal Question in Business Law in California

It would be a waste of your money to have a lawyer write a letter when the landlords have done nothing legally wrong. in fact, if they are paying you $35/day for a $200/mo diminished value, they are paying more than they owe you, unless your lease calls for $35/day in the event of construction or repairs.

As for the meaning of per diem, as I told you, it literally means nothing but "per day." Its most common usage is in the employment context, hence some of the questions I mentioned in response to your first question. In that context it has a very specific meaning - which is a fixed amount paid per day to an employee who is required to work away from home, in lieu of paying actual out of pocket expenses. The Labor Department and the IRS maintain annually updated tables of the per diem rates for various metropolitan areas. Many state agencies maintain their own tables too. Initially these were developed for government employees as a cost saving measure when government employees had to travel. The idea being the employee should only be compensated for the difference between the cost of being home and the cost of being on th road, not the full out of pocket expense. These quickly caught on both as agencies that used a lot of contractors started requiring reimbursement by per diem instead of out of pocket for expense billing under their contracts, and as private employers with large travel budgets saw the cost savings. That is the usage of "per diem" that you are turning up on your web searches. It has nothing to do with your context. In your context, per diem means the per-day loss of value to you of having your unit, and being put in another unit instead. That is not a per-person per-diem, like when an employer sends two employees on the road, it is a per-unit per-diem.