Qualcast mowers are pretty decent, real bargain that. Used to be owned by Bosch now they are just basic Chinese made with the Qualcast name licensed but they weren't mega money new when they sold them through Homebase. New it would have been £250ish and they had the Briggs 300 so good reliable engine.
You will never find cheap mowers on Facebook or anywhere, around where I live in Oxfordshire, your mum must be happy with a few more mowers in her garden