You should ask Marriott Rewards if it would be possible for you to get a platinum or gold challenge. If they agree, you will have 3 months to stay a certain number of nights, usually 15 for gold and 18 for platinum. This status will be for just the year you finished the challenge, and you will have to earn the required nights to maintain status for the following year.

You should also sign up for the Marriott Premiere Visa since it will give you 15 nights elite credit each year you have the card.