No insurer transacting a mobile home insurance business in this State and writing hazard insurance covering loss from physical damage to the mobile homes may issue a policy for more than the value stated in the policy or the value of the property to be insured. The amount of insurance must be fixed by the insurer and insured at or before the time of issuing the policy. In case of total loss as a result of a hazard insured against, the insured is entitled to recover the full amount of insurance. In case of partial loss the insured is entitled to recover the actual amount of loss but in no event more than the amount of insurance stated in the contract. If two or more such policies are written upon the same property and covering the same interests, they are considered to be contributive insurance, and, if the aggregate sum of all such insurance exceeds the insurable value of the property, as agreed by the insured and insurer, each insurer, in the event of a total or partial loss, is liable for its pro rata share of insurance. This section does not preclude an agreement by an insurer with its insured to effect replacement in the event of total loss of the mobile home as a result of a hazard insured against if the insured has maintained insurance of a given percentage in relationship to the market value of the mobile home.