Crate or xpen for a 6 month pup while I’m at work?

With gradual introduction, either option will work. If your dog has separation anxiety, I would recommend the crate since it's more secure. I have a Great Dane who just turned 1 and we have used a 48 inch high xpen for him since he was 9 weeks old (when no one is home). He could tip it if he really wanted to but he settles down and gets comfortable very quickly after he goes in and it's more spacious than the crate would have been. A frozen peanut butter kong each time you put her in would be a good way to help your pup get acclimated to either the crate or xpen. That way there is a positive association.

Since she will have some new changes, I'd recommend you contact sitters and ask if they'd be willing to offer daycare at a special rate for 5 x a week if booked weekly. It may not be much more than 2x/week. Then later, you can re-visit the crate or x-pen purchase. The sitter may even be able to share their advice if they ever use a crate or x-pen (when unobserved for the pup's safety). Alternatively,if you only want to do day care 2 x/wk., you could ask that sitter if they could do a drop in visit or walk the other 3 days that you're working.

Crate training is done gradually, with rewards (never as a punishment) so the dog looks upon the crate as their own cozy den/hide-a-away. This article does a good job explaining crate training. http://www.humanesociety.org/animals/...