Answer:
Having a deadbolt lock installed on the exteriors of a building would affect the price of Insurance.
The principles of insurance require that the Insurance Policy Holder or Insured should act as if uninsured. This means that even with an Insurance Policy in place, the owner of this house is required to ensure that all reasonable steps have been taken to secure the house.
This may include having a properly installed lock in place.
The price or insurance premium of a homeowner may go up very significantly if there is no lock installed, that is if the risk is accepted for coverage by the insurance company.
It (the premium that is) may or may not come down if there is a deadbolt lock in place. It all depends on the extent to which the deadbolt lock has reduced the exposure of the Insurance company. Where the deadbolt lock has very significantly reduced the risk, the policyholder may press for a reduction in insurance premium.
In most Homeowners Insurance policy, for a claim concerning theft of insured home items, the policyholder has to provide evidence of forceful entry or exit, showing that the house was reasonably secured to warrant a breaking in or breakout.
Cheers!