Over the years having lost an 80hp tractor, trucks, a skid steer + other gear to theives so it's a case of deterring rather than prevention as the most determined thief will find a way but most like a quick quiet snatch & grab so anything you can do to add noise & time to the exercise will work in your favour.
Depending on the isolation of the sheds/farms we may use any/all of the following on our farms as deterrents:-
1. Sensor Lights
2. Motion detector/back to base alarms
3. Beam alarms on an all entrances/gateways
4. Concealed CCTV wireless recording camera's/visible signs advising of their use & that the property is perimter alarmed
5. Remove batteries from gear that is not being regularly used
6. Concealed battery isolation switches
7. Chains/industrial pin type padlocks on implemements. Always chain mutilple implements together with long lengths of chain doubled back so each implement has two chain lengths running through it & use multiple padlocks at intervals along the total length of chain - the more padlocks the better + thread large steel vehicle wheels & tin cans along the chain - this makes for one noisy/time consuming exercise for any thief....
8. Dynabolt small engine, gear & implements to concrete floors (some by using pivoting steel pipe bent to fit over the equipment & secured to the dynabolt by shielded padlocks)
9. Security locking vertical posts/horizonal bars
10. High tensile barb wire strained "gates" (sure you can cut it easily but at night under extreme tension it's going to hurt bouncing around, works good on visible hay sheds close to roads)
11.Concealed low cost "tilt" scream alarms on individual "hand" transportable gear
12.If implements are only used seasonally we have on occasions welded them together with scrap/offcut steel
13. Park mobile wheeled gear like tractors, mowers, trucks etc further back from any access & behind implements
14. Big Guard dogs