Then early on Friday morning, a Kawasaki quad bike was stolen from a farm near Matamata.
On the same day, three dirt bikes including a Husqvarna 650cc bike, valued at $6000, and two Suzuki 200cc bikes were taken from a padlocked container on a Mangateparu property.
In Te Kauwhata, about 10 farm vehicles have been taken from properties in recent days.
Rural residents were not the only victims, with a Hamilton business also being targeted.
On Monday, a worker at a commercial property on Te Rapa Rd found a locked shed had been forced open.
Two relatively rare vehicles had been stolen - a 2009 Yamaha Raptor special edition quad bike with only 18km on the clock, which was worth about $9000, and a 2010 yellow Suzuki RM125 motor-cross bike, worth about $5000.
The Suzuki had the tip of its clutch handle broken off and had recently undergone an engine rebuild.
Ms Grace said police wanted to hear from anyone who had been offered a deal on a farm vehicle that seemed too good to be true.
Stolen bike sellers could target the farmers they sold them to, stealing the bike back along with other farm equipment.
"Receiving stolen goods not only puts you at risk of prosecution it places you at risk of also becoming a victim, not to mention costing us all in increased insurance premiums."
Ms Grace said quad bikes were also used by cannabis growers.
She called on farmers to look out for suspicious vehicles in or around properties.
Ms Grace said anyone with information on the thefts, or who has seen any suspicious activity, should contact police.
She urged owners to secure their farm vehicles by locking them away out of sight, and removing the keys from the ignition.
"A moment's inconvenience can mean the difference between keeping your valuable investment and it coming into the clutches of dishonest, opportunistic thieves."