So my 2 dogs have always been allowed to roam the backyard. Now they have started digging random holes trying to bury toys. I took the toys away and they started finding other crap to chew/play with. I take too much pride in my yard to have this crap going on. Plus it's getting expensive.

So kennel time. I was thinking of going to the farm and ranch store and buying some cattle panels and fence posts. I have two spots i can put it. One is approx 30feet from the back porch in the back corner of the yard. I would only have to construct 2 sides as the cedar fence is already there. Problem is they may try and dig under it (they have not tried yet). Also, i would have to run 110v out there.

Second place is right next to the house behind the attached garage.  110v is close but I would have to construct all sides of the kennel.

They have a nice insulated dog house to use so that is taken care of. Heated water bowl is also available.

Any other suggestions? Construction wise, etc?

How big of a kennel should I build for one medium and one large dog? Wife and I are gone up to 12hrs a day so they need a little space to play. If I build it in the back corner, there is more room for a larger kennel. Behind the garage I don't have as much room.

I have access to gravel, Should I throw down a layer of 3" minus? I can put some 1x6 around the bottom of the panel to keep it in.

If they would use the sandbox I'd build it.  I just don't know if they would or not.