Something is known about the burglar in 45% of cases. In this rather invasive crime, half of burglaries are betrayals of trust or familiarity. More than a few of these burglaries might be committed by family members and friends wanting money for drugs but that is speculation.
Source: Home Office via What burglars steal – and how they get in | News | theguardian.com.
Source: Education at a Glance 2015, section 6.
Still have not seen a decent explanation for why German housing prices seem to fall for decades on the trot.