You can get a 500 foot long spool of Cat6 underground off Ebay for about $80. Ether crimp on a RJ45 on each end or put a Cat5 Data jack on both ends and use jumper's.
I started with Verzion FiOS back in 2007 up in Redmond WA. 1,000's of installs were just "Spade Cut" 3 inches deep. I had to splice 100's when homeowner thought they were deeper and cut them. The light is invisibale but VERY strong and will burn you and do major eye damage. It is like +14Db. One cut fiber cable did set some straw grass on fire.