Charterhouse’s summer classic car auction promises to be a sale of variety and unquestionably high quality when it takes place on June 27

Once again, the location for Charterhouse’s next sale will be the Haynes Motor Museum in Sparkford, Somerset, with viewing available on the morning of the sale.

Convertibles are a major theme as summer approaches, the rarest likely being a striking 1934 Lagonda Rapier. Resplendent in light blue over dark blue with a matching blue leather interior, it carries a £30,000–35,000 estimate. A 1987 Mercedes R107 300SL offers glamourous Teutonic cruising in Champagne Gold for an estimated £16,000–19,000, while a 1989 Porsche 944 S2 Cabriolet offers German quality in a sportier Guards Red package for an estimated £12,000–14,000.

British drop-tops are plentiful too, with everything from a charming 1936 Austin 10 Clifton Tourer at an estimated £6500–7500, to a maroon 1978 MG Midget 1500 that was recently treated to £11,000-worth if expenditure for a very reasonably estimated £3000–4000. Meanwhile, a 1993 Jaguar XJS 6.0 V12 Convertible in Topaz Gold offers glamour to match the R107 SL and carries a £20,000–22,000 guide. Prefer a sportier convertible? There’s a 1995 Lotus Elan M100 S2 with just 52,000 miles on the clock for an estimated £7800–8200, a 2002 Porsche Boxster with the preferred manual gearbox that carries a £5000–5500 guide, and a 53,000-mile 2000 Alfa Romeo Spider TwinSpark for an estimated £2800–3200.

If you prefer something family-friendly, there’s a very rare 1988 MG Maestro in 2.0 EFi guise, while a 1981 Ford Cortina Mk5 2.0 Ghia that was a previous in Classic Ford cover star has a £7000–9000 guide price, and a 1983 Mk2 Granada 2.8 Ghia X Estate offers the ultimate in 1980s Ford luxury for an estimated £7000–8000. A 1964 Wolseley 1500 in a lovely shade of primrose yellow and sporting a handy MGB twin-carb conversion offers a more traditional yet still useable classic for an estimated £2500–3000, and a 1967 Morris Minor Convertible is reasonably guided at £8000–10,000.

A classic auction wouldn’t be complete without some rarities, and Charterhouse delivers. A 1948 Bristol 400 is one of just 487 ever made, and is said to be in excellent mechanical and cosmetic health, all justifying a £38,000–42,000 guide price. Amongst Triumph TR enthusiasts, a TR2 is one of the rarest models, making the 1956 British Racing Green car in this sale likely to attract plenty of attention with its £18,000–22,000 estimate.

However, the 1905 De Dion Bouton Type AL 8HP makes the TR2 look common – with just four owners in its 119 years and practical upgrades including rear disc brakes, 12-volt electrics, an electric fan and a Zenith carburettor, it’s estimated at £22,000–25,000. For the full catalogue of entries, head to charterhouse-cars.com