The Subscription or ending of a letter consists of the term of respect or affection and the signature. The term depends upon the relation of the person addressed. Letters of friendship can close with such expressions as:
Yours lovingly,
Yours affectionately,
Devotedly yours,
Ever yours, etc.
as between husbands and wives or between lovers. Such gushing terminations as Your Own Darling, Your own Dovey and other pet and silly endings should be avoided, as they denote shallowness. Love can be strongly expressed without dipping into the nonsensical and the farcical.
Formal expressions of Subscription are:
Yours Sincerely,
Yours truly,
Respectfully yours,
and the like, and these may be varied to denote the exact bearing or attitude the writer wishes to assume to the person addressed: as,
Very sincerely yours,
Very respectfully yours,
With deep respect yours,
Yours very truly, etc.
Such elaborate endings as
"In the meantime with the highest respect, I am yours to command,"
"I have the honor to be, Sir, Your humble Servant,"
"With great expression of esteem, I am Sincerely yours,"
"Believe me, my dear Sir, Ever faithfully yours,"
are condemned as savoring too much of affectation.
It is better to finish formal letters without any such qualifying remarks. If you are writing to Mr. Ryan to tell him that you have a house for sale, after describing the house and stating the terms simply sign yourself
Your obedient Servant
Yours very truly,
Yours with respect,
James Wilson.
Don't say you have the honor to be anything or ask him to believe anything, all you want to tell him is that you have a house for sale and that you are sincere, or hold him in respect as a prospective customer.
Don't abbreviate the signature as: Y'rs Resp'fly and always make your sex obvious. Write plainly