Hi. I hope somebody can answer this one. My contractors are reluctant to put in central HVAC units on houses we are rehabbing or building new until an offer is made on the house since they say the units will be stolen, especially since the copper components are now valuable because of the high price of copper. From boot camps and seminars, I've been told that the house has to be in immaculate condition for it to sell to retail buyers. Our houses are not in war zones but my contractors say that thieves are stealing outdoor central HVAC units even in the best neighborhoods here. Is there a way to install outdoor central HVAC units such that they can't be stolen or are my contractors correct in not installing them until offers are made on our houses? TIA.