Can't fault a man for rising to a challenge....
I'm sorry I have no idea where he was living in Leeds just that both sons were wed in Leeds Parish Church. Prior to this the family were living in York and I have no idea when they moved to Leeds or how long they lived there (I do know they had gone by 1843)
Charlotte Severs (the wife of William) was also born in York, which begs the question did her family move to Leeds also?
Mary Ann Wood, the wife of Robert Leng, was born in Leeds (c.1819), daughter of Thomas. I'm awaiting the marriage certificate of Robert and Mary Ann to get the occupation of her father and whether he was still alive in 1840.
I don't know whether there are any trade directories that might list the family. John (snr) was a shoemaker or cordwainer and all the sons were engineers
I hope you can help, Brian....there's Leng devotees all over the globe counting on a favourable outcome....geeeeeezzzzz