Landlord/tenant question. What can we do about this.?

We live in Reno Nevada, We moved into a duplex managed by a "rental company" We moved in on the first of July 2007. The manager has a maintainence guy (I'll call him Al)that collects rents, fixes things, and handled our move in. Al was supposed to bring a rental agreement or lease but never has. He kept asking for the deposit money, but my better half refused to give a deposit with out a lease or a rental agreement.... We have always paid our rent on time, however we were late this week and Al came over about 8:30 at night threatening to kick us out... The chick next door is consistantly late...nothing happens to her. She also says she didn't sign a rental agreement. It seems to me that something is really fishy here... Can this company kick us out for late rent if they refuse to furnish a rental agreement?