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You have a Singer model 27 from 1910. The Singer Model 27 and later model 127 were a series of lockstitch sewing machines produced by the Singer Manufacturing Company from the 1880s to the 1960s. (The 27 and the 127 were full-size versions of the Singer 28 and later model 128 which were three-quarter size). They were Singer's first sewing machines to make use of "vibrating shuttle" technology.
Regarding the value of your item, I have just perform a market research of similar sold items as yours. I performed the research based upon the most recent finished auctions and private sells, so the value given is the real market value of your item. This is the only way to know the exact value of your unit.
The value will be in the range of 150-200$ if in good working condition.
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