Generally a job offer letter will show your new salary and that will help that you will be financially able to pay rent. And if they refuse at first, they will often accept if you offer to pay the first few months of rent in advance.You can also use an official offer letter as proof of income as long as it includes your salary. Formally accept a job offer with our job acceptance letter template. Craft a professional job acceptance letter to start your new role positively. In California, you'll need to fill out a form that covers your rental and employment history, income details, and references. A sample letter offering a job contingent upon the results of a background check or other criteria. According to MassLandlords. Net, an offer letter is a common method of verifying income. Follow up in writing: It is a good idea to follow up with an email or letter to confirm your acceptance and all the details of the offer.