First off, do you have his 1912 arrival at Detroit, Michigan?
contact in England: his father Robert, 133-9 Finsburg [something], London
destination: friend H L Kutler, Hamilton, Ohio
https://www.familysearch.org/ark:/61903/1:1:QK3Y-TSY2familysearch is free, but you need to set up an account.
2) I see you have a tree on ancestry that says his mother's name was Neuburger. Did you notice on the outgoing passenger list in 1937 that there is a William Neuerburg on the same sheet? Is this a relative whose name is misspelled or coincidence? Mr Neuerburg is listed just below Renould on the incoming passenger manifest, and they were headed to the same hotel. However, they did not get their passports on the same day, nor were they intending to stay in NYC for the same length of time. -- Just mentioning it in case you want to take a look.
3) The Windmill Arkley was his home address. Here is a transcript of the whole thing and a link to the image. Again this is a free site, but you need an account:
left Southhampton 22 October 1937, arrived New York 30 October 1937, on the SS New York, Renold Marx, 48, male, engineer, able to read English, French, German, nationality: Great Britain, born in London, last residence: London
Nearest relative in England: wife, Mrs Marx, The Windmill Arkley, Herts, England
Final destination: London, passage paid by employer, had been in US before in 1913 for 6 weeks, In N.Y., destination in US: Waldorf Astoria Hotel, NYC, intends to stay 60 days and return to England, does not intend to become a citizen of the US
physical description: 5 feet 6 inches, fair complexion, grey hair, gray eyes, no distinguishing marks of identification
traveling with, maybe: William Neuerburg, 42, a manager, born in Uccle, Belgium, last residence: London
sister: Mrs G Dawson Harris, 47 Queen's Gate, S.W.7
https://heritage.statueofliberty.org/passenger-details/czoxMjoiOTAxNzU5NDIxMTkwIjs=/czo4OiJtYW5pZmVzdCI7----------
That done, here's why we can't find his death:
London Gazette 25 November 1938
Notice is hereby given ...
on the 23rd of November 1938 Renold Marsh of "The Windmill" Arkley near Barnet in the county of Hertford Engineer a natural born British subject renounced and abandoned the names of Renould Marx otherwise usually known as Renold Marx.
.. Solicitors for the said Renold Marsh
https://www.thegazette.co.uk/London/issue/34574/page/7495/data.pdfcan't post the image since this is the lookup board? any suggestions anyone?
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so here is his death, from freebmd.org.uk
Deaths Sep 1972 (>99%)
Marsh Renold 24De1888 St.Marylebne 5d 1779
