"Siemens codes (SIE / 7346) are among the most reliably active corporate codes, showing 15–22% discounts at many global Marriott properties. The code appears in widely distributed PDF documents traceable to 2014. If you are caught, the property can raise your rate to the current rack rate and you could be considered to be defrauding the property. Wide documentation suggests this code has been in circulation for over 10 years."

"I don't do mobile check-in if I'm wanting to upgrade. I check the app before I go in to see if any suites are available to book during the duration of my stay. If there is I just say "Would it be possible to get upgraded to an available suite with my platinum benefit?". Of course this is typically at the hotel that I stay in about once a month for 3 day at a time for work. The front desk pretty much knows me and know that I am fairly low maintenance."

"I occasionally try to get the corporate rate for a company I'm visiting in the area (for sales/consulting). Only once has a front desk clerk asked me to prove my eligibility, and she was satisfied by me giving the name and telephone number of the person I was visiting."