Request advice on safely accepting a large check

Hi,

My late sister's mobile home sold rather quickly, and my parents are sending me the title to the home, which I will exchange for a sizable check.

The sale of the house was handled by my sister's mobile home park, and the check is being issued by this park, and not by an individual.

How do I protect myself from screwing up and trading the title for worthless paper?

Thanks in advance,

-Boyd