First, you should read this post for crate size guidelines and how to measure your dog.
The first crate we got, a long time ago, I found at a garage sale. It’s was used for our Chocolate Lab for a few years from the time he was a puppy. When we left the house, we would tell him to go to his ‘house’ and he ran to it because he knew he would get a treat.
When he got older and bigger, there was no need to lock him in the crate. But to this day (he’s now 13) he still sleeps in it on and off during the day and the door is always open. I felt the crate was too small for him, so I bought this one from Walmart.
When we fostered and then adopted Yuki the Husky mix, he was 10 months old and he was a counter surfer! We couldn’t leave any food out because it would be gone in seconds. We also had to hide and put away any socks, as he did eat a few!
So we trained him to use that same crate also when we went out.
Here are a few examples of the different kinds of crates available from Amazon.