A 20,000 sq ft marquee will be erected in Dorsington, Warwickshire, to disperse the eclectic contents of a dozen properties. The three-day sale on September 29-30 and October 1 will number close to 2500 lots with an estimated value of £1.5m-2m.
Dennis, a former editor of counterculture magazine Oz, whose company later pioneered computer and hobbyist magazine publishing in the UK, owned homes in New York, London and Mustique as well as his estate in Dorsington.
With collecting interests ranging from period oak and walnut via tribal art, marine antiques and Modern British sculpture, Dennis bought occasionally at auction but - as surviving invoices attest - primarily from dealers in the Cotswolds in the 1970s, '80s and '90s. Most lots in the sale will have expectations in the mid hundreds with an 1845 Garrard silver racing trophy carrying the top estimate of £60,000.
Bigwoods' proprietor Christopher Ironmonger has a longstanding relationship with the Dennis estate and was the first point-of-call for the executors. He brought in Halls on a 50-50 basis to tackle what has proved a mammoth clearance.