I like the life stages crate the best. it is collapsable for traveling, and there are 2 different openings for either a front entry or side entry, which is great for trying to squeeze a crate in a small apartment. the lock on the crate can be opened. my dear tango did not take long to figure it out. we bought the small rope climbing type clips at REI and now he can not get out of the crate! Another idea that has worked for us is to leave dirty laundry in the crate when you are away. It might sound crazy, but it has worked for me. I put on a sweatshirt and pair of socks i could live without, went to the gym, did some yard work, cleaned the house (made sure my odor was there!) i tied the socks into a knot, and threw the sweatshirt in the crate the socks became a favorite chew toy and as for the sweatshirt, a favorite pillow. Good luck!