Wow, here in England, pretty much any house you buy has a fence, I don't think they build them without them these days, so I'm not sure how much a fence costs. My fence is just wooden boards linked together by concrete pillars. Riptide's idea of blocks with wood through them seems a good idea, providing they can't be squeezed under of jumped over, chicken wire could help but there's a possibilty Roxy could chew through it if she wanted to. Sorry I'm not much help. I'll think about it a bit more for any ideas