Ransomes Marquis mk.4A
These machines are overall probably the best domestic cylinder motor mower of all time. This well used, but not abused, 20" example was in regular use until relatively recently and is still a reliable starter and runner. It has a home-made long grass conversion but this could readily revert to normal front rolls if required.
The famous ' sloper ' engine has a very pleasing slow tick-over and while not having smart paintwork this mower is ready for work, perhaps with a little t l c. As I am often saying to people - a fancy paint job won't make it cut grass any better.
Update - some interest being shown in this machine, so if you are interested don't think about it too long !