877-861-0838

Looks like one of those advance fee business loan places, guaranteeing $250,000 with a fake check attached to the mail.

NATIONAL MERCHANTS CAPITAL
Posted in:  https://800notes.com/Phone.aspx/1-877-861-0838
Web site gives no physical address:  http://www.nationalmerchantscap.com/contact_us.html
LinkedIn page says they are in the Miami/Ft. Lauderdale area:  https://www.linkedin.com/in/nationalmerchantscapital
Face book page gives no relevant information, but they do claim they will give large amounts to businesses with bad credit.  What lender does that with no collateral?    None.
https://www.facebook.com/pages/National-Merch ... 22371631?ref=hl
Now here is the kicker.  They are not registered with the state of Florida as a corporation as required by law.   They are not registered with the Florida Dept. of financial Regulation as required by law.  They are not registered in any state as required by law.

Best bet is to turn the letter and the envelope over to the postal inspectors.