The family were laid to rest near their Shropshire home in December
A businessman thought to have killed his wife and daughter before torching their mansion was in "severe financial difficulty", an inquest has heard.
Christopher Foster's thermal insulation firm Ulva Ltd went into liquidation in October 2007.
Police believe he killed Jill, 49, and Kirstie, 15, before burning their £1.2m home in Maesbrook, Shropshire.
A Home Office pathologist said Mr Foster probably died as a result of smoke inhalation in last August's fire.
Police opened a murder inquiry after tests showed Mrs Foster had been shot in the back of the head.
A gun owned by Mr Foster and spent and unspent cartridges were found scattered around the kitchen, driveway and 16-acre grounds of Osbaston House.
The family claimed kidnap threats had been made in respect of Kirstie
Firearms expert Dr Phillip Rydeard told the inquest that pieces of lead and bullets found in Mrs Foster's skull and that of her daughter Kirstie "were consistent with having originated from" a German made .22 bolt action rifle, which had been fitted with a silencer.
Pathologist Dr Alexander Kolar told the hearing at Shrewsbury Magistrates' Court there was no evidence that Mr Foster had died of a gunshot wound.
He said Mr Foster would have been alive during the fire, but probably died in "tens of minutes" from breathing in smoke.
His body was found lying on top of his wife in a room below their bedroom.
Stephen Langton, representing Mr Foster's brother Andrew and mother Enid, said the family believed there had been kidnap threats made against Kirstie Foster.
He said Peter Day, a lorry driver from a nearby animal feed company, saw three men "loitering at the property" on the morning of the fire.
Mr Day asked a colleague to raise the alarm after spotting an "orange glow" from the road leading to the five-bedroom house and firefighters were called at 0430 BST on 26 August and quickly alerted police.
Under cross-examination, Det Con Paul Rogers of West Mercia Police was asked whether police were aware of the kidnap allegations and the witness.
The £1.2m mansion was destroyed in the fire
Mr Rogers said officers had no witness statements to such effect and had only learned of the claims on Wednesday evening, but said the force would investigate.
The two-day hearing was also told the ruined millionaire had told police in December 2005 his ex-accountant was blackmailing him over a joint property deal in Cyprus.
Two people were found not guilty at Shrewsbury Crown Court in November 2006.
The inquest was shown photographs of the property, which was monitored by three CCTV cameras, before and after the blaze.
Photos of the property's dining room also displayed containers of heating oil on the floor.
The hearing was told an oil tank used to heat the property was situated in the outbuildings of the house and would have been full at the time of the fire.