Do I marry the Janitor?

I am a divorced professional woman in my 40s, not a lot of luck in the love department although I am very nice, but here's my situation: the maintenance man where I work says he is in love with me. He is 67, but looks 57: Very clean, articulate, we actually have a lot of similar interests. He wants me to marry him and says he will sign his house over to me and also give me $20,000. I am wondering what I have to lose: it's not like I am going to get married and have babies at this age and I am sure I could do worse things in life than give an old man some pleasure for a few more years. He loves to travel and eat out, says I will have no worries about money because he will take care of my every need. I am not thrilled about having to get naked with him, but there are sacrifices in every relationship and I do like him as a person. Am I prostituting myself if I do marry him for convenience and security?