The Danish home inspection scheme is a trade: the seller is released from the usual 10-year liability for hidden defects, and in return you get the reports and an insurance offer. The trade only holds if all four conditions in lov om forbrugerbeskyttelse ved erhvervelse af fast ejendom § 2 are met.
1. A valid tilstandsrapport
At most 6 months old on the day you receive the purchase agreement. Older than that, the seller must have it renewed.
2. A valid elinstallationsrapport
At most 12 months old on the same day.
3. An insurance offer
A binding offer of ejerskifteforsikring you can take out before taking over. It must come with the purchase agreement.
4. The seller pays at least half the premium
The seller must offer in writing to pay at least half the premium of the basic policy offered. You may choose another insurer; the seller's share stays the same.
If one condition is missing
Then the seller is not released, and you can claim hidden defects against the seller for up to 10 years. It sounds like an advantage, but it is an uncertain road: the seller may have moved, died or have no money, and you carry the case. Most buyers are better served by all four conditions being met, and by taking the insurance.
What the seller remains liable for
Fraud and gross negligence, matters outside the reports' scope (drains and service pipes, the plot, oil tanks, contamination, unlawful buildings) and guarantees given in the sales material, such as "fully renovated".
How to check
Tjekhuset's full report reads the validity of both reports from the documents and shows the two conditions you must find in the purchase agreement yourself.