>Never ran a company
Does a historian have to travel back in time to write history?
>Never held political office
Most European countries openly persecuted Marxists at the time. Even in "liberal, democratic" Britain the police would keep a close watch on Marx's whereabouts throughout his life.
>Never oversaw any accounts
He did have to manage money in order to maintain newspapers, which brings us to...
>Never even held a job
He was an editor and journalist. He contributed nearly 500 articles to the New-York Tribune, one of the most important American newspapers at the time. Besides this he also helped in organizing the affairs of the International Workingmen's Association.
>his friend Friedrich Engles, the son of a wealthy factory owner
Besides the typo (Engels, not "Engles"), I fail to see the relevance. Engels corresponded with Marx every other day, they worked out Marxist theory and what books and articles Marx was to write. Engels was with Marx almost from the start of their careers as revolutionaries.
If Marx should be ignored because he didn't run a company, then using the same silly logic every anti-communist should zealously read whatever Engels wrote since he must have been a glorious economist by virtue of being the son of a capitalist and running a factory at one point.