I'm sorry to hear about the death of your partner. Triumph Spitfires are tough little cars, although like any classic they suffer if neglected. The good news is that mechanically they're very tough - so one of the biggest factors that will determine price will be the condition of the bodywork. Just to give you an idea of value, one of the very best examples of these on sale at a dealer's would be priced at around £8500, while a similar example for sale privately might be up for £6000. A car that's running but in need of some TLC would be about £2500 while a project that's been off the road for a number of years will be about £1200. I imagine that your car will be somewhere in between the lower two values, depending on the bodywork. In terms of how to sell it, you've got several options. If you want to minimise hassle, then selling the car at auction is probably the way to go - but be mindful that the price you sell it for will likely be lower and there will be additional fees to pay. If you want to get the most money then selling the car privately will be the way to go - but you will have to deal with all the hassle of writing an advert, taking pictures, uploading it to various sites or sending it to magazines and - of course - dealing with inquiries.