Perhaps you already know this, but Penthouse 38 is not owned or operated by MGM Resorts. This appears to be a company that offers short-term rentals for the units they own within the Signature towers.
According to the website, there is no housekeeping. They don't allow early check-ins or late check-outs. They even state that you will be "charged $25 per each half hour beginning at 11:30 A.M" on your departure date. Additionally, You must pay in full 14 days prior to arrival. A damage deposit of $250 is also required. If you cancel or shorten your stay, you get no refund and they keep that $250.
My favorite restriction: If you have any maintenance issues, you're supposed to email the owner. Apparently he only accepts calls "if it is an EMERGENCY (only)".
I don't care what the rate is, I'd never agree to all those restrictions when there are so many other options in Las Vegas.