Harman married Elizabeth Brouwers in New Utrecht. They probably moved to Bensalem Township in Bucks County, Pennsylvania, with his father in 1699.
He purchased 250 acres of land in Bensalem Township on August 1, 1704. In 1711, he purchased 50 acres in Southampton, which he conveyed to his brother Jacobus. On April 26, 1712, he bought 250 acres more. He then bought another 125 acres from his brother, Johannes, on May 26, 1713. On May 20, 1741, he purchased another 100 acres.
In 1724 Herman Van Sandt is a deacon of the church, he is noted as having had a difference with Abraham Vandergrift but now are reconciled. Churchville, Pennsylvania Session and Register were his children are baptised. These records are in de Deutsch. 
Harman Van Sandt died in Bensalem Township in 1759.
before June 10, 1674 in New York
June 10, 1674 in New Utrecht, Kings, New York
10 JUN 1674 Dutch Reformed Church, New Amsterdam (New York)
Husband of Elisabeth Brouwers — married in New Utrecht, Kings Co., NY
Husband of Jeanne Jaudon — married February 8, 1733 in First Presb. Ch., Philadelphia, PA
Husband of Judith Evans — married November 9, 1738 in Abington, Presbyterian, Bucks Co., PA
He had five children:
Garret (d. 1755);
Gazina (m. Jacob Titus);
Elizabeth (m. Volkert Vandegrift);
Katherine (m. Daniel Severns);
Harman (m. Alice Craven).
Land Records - All in Bensalem, Bucks, Pennsylvania
1 Aug 1704 - Thomas Stevenson, yeoman, of Bucks Co, PA to Harman VANSANDT, yeoman, of Bensalem Twp, Bucks Co, PA, 200 lbs., 250 acres Bensalem Twp line of Joseph Growdon and Johannes VANSANDT. Signed Thomas Stevenson. Wit: Jonas VANSANDT and Adolfas (x) Bruer. 
1 Jan 1712 - Harman Vansandt, yeoman, of Bensalem, Bucks PA to Jacobus Vansandt, yeoman, of Southampton, Bucks PA, 50 lbs., 60 acres line of John Collins. Signed Harman Vansandt. Wit: Thomas Walmsley & James Vansandt.
26 Apr 1712 - Thomas Stevenson, gentleman, of Bensalem, Bucks PA, to Johannes Vansandt, yeoman, of same, 75 lbs, 125 acres line of Harman Vansandt & Joseph Growdon. Signed Thomas Stevenson. Wit: John Robinson, Johannes Vansandt & Jeremiah Langhorne.
Same date: Thomas Stevenson, gentleman, of Bensalem, Bucks PA, to Harman Vansandt, yeoman, of same, 150 lbs, 250 acres. Wit: Jeremiah Langhorne & Johannes Vansandt.
26 May 1713 - Thomas & Sarah Stevenson, yeoman, of Bensalem, Bucks PA, to Harman Vansandt, yeoman, of same, 130 lbs., 125 acres line of Joseph Growdon purchased of Johannes & Lea Vansandt. Wit: James Smyth, Edward Kempe & Jeremiah Langhorne.
13 May 1714 - Harman Vansand of Bensalem, gent., and Elizabeth his wife, for Lb. 29.15s, to Thomas Stevenson of the same place, gentl, a tract of land containing 29 acres and 3 rods beginning at a stone about a gunshot below the dam on the west side of the Run. Said land part of a piece of land which Thomas Stevenson sold to Harman Vansand. Made 13 May 1714. Wit: James Smyth, Jeremiah Langhorne. Ackn 31 May 1714. JP: Francis White. Rec. Deeds: Jeremiah Langhorne.
1759 in Bensalem Twp., Bucks, Pennsylvania
May 9, 1759 in Bensalem, Bucks, Pennsylvania.
1674 Jun 10 Herman - Gerrit Stoffelszen, Lijsbeth Gerrits. Wit.: Geen getuijgen. 
1704 May 28 Gerret - Harme Gerritze, Elisabeth Brouwer. Wit.: Abraham Brouwer, Jannetie Brouwer.
1710 May 21 Jesyntye - Herman Van Sandt, Elisabeth Brouwers.
1733 Dec 08 Van Sandt, Herman, and Jane Jondon. 
1738 Nov 09 Vansandt, Harman, and Judith Evan. 
He married first at probably Brooklyn, Kings Co., New York, circa 1697 Lysbeth Brouwer, daughter of Willem Brouwer and Elizabeth Simpson.
Harmen Gerretsz van Sant married second at Abington Presbyterian Church, Bucks Co., Pennsylvania, on 9 November 1738 Judith Rowland, daughter of Rowland. 
There is no mention of a third wife. The sources for Judith in "The Brouwer Genealogy Database" are:
Barbara A. Barth, "The Van Sant Family of New Utrecht and Bucks Co., Pennsylvania", New York Genealogical & Biographical Record Vol.127, no. 3, p. 129 (1996): 127:233. Hereinafter cited as "Van Sant Family of New Utrecht and Bucks Co., Pennsylvania."
George E. McCracken, "Cornelius McCarty and Judith Rowland of Bucks County, Pennsylvania", The American Genealogist Vol. 47, page 166 (1971): 47:167. Hereinafter cited as "Cornelius McCarty and Judith Rowland."
"Jeanne Jaudon (Pierre8, Daniel4, Pierre2, Francois1) was born before 8 Apr 1711, was christened on 8 Apr 1711 in Dutch Reformed Church of Bensalem & Neshaminy PA,1 and died before 9 Nov 1738.
Jeanne married Harman Vansandt, son of Garrett Vansandt and Lysbeth Gerritz, on 8 Feb 1733 in First Presbyterian Church, Philadelphia PA. Harman was born before 10 Jun 1674, christened on 10 Jun 1674 in Dutch Reformed Church of New York, and died in 1759 in Bensalem, Bucks PA." 
↑ 2.02.12.22.32.42.5 Abstracts of Buck Co., PA Land Records, 1711-1749. Deed Book A, Vol. 3, p. 190. Deed Book A, Vol. 4, p. 237-238. Deed Book A, Vol. 5, p. 19. Deed Book A, Vol. 2, p. 41.
↑ 3.03.1 Thomas Grier Evans. "Baptisms from 1639 to 1730 in the Reformed Dutch Church, New York." In Collections of the New-York Genealogical and Biographical Society. Vol. II. New York: Printed for the Society, 1890.
↑ "Pennsylvania Births and Christenings, 1709-1950," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:V2V2-H4P : 9 December 2014), Jesyntye Van Sandt, 21 May 1710; Christening, citing REFORMED NETHER DUTCH CHURCH, SOUTHAMPTON, BUCKS, PENNSYLVANIA; FHL microfilm 20,338.
↑ "Pennsylvania Births and Christenings, 1709-1950," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:V2NF-8PP : 9 December 2014), Herman Van Sandt in entry for Cornelia Van Sandt, 23 Jun 1714; Christening, citing FIRST PRESBYTERIAN CHURCH, PHILADELPHIA, PHILADELPHIA, PENNSYLVANIA; FHL microfilm 974.8 B2P V.19.
↑ 6.06.1 John Blair Linn and William Henry Egle. 1895. Record of Pennsylvania marriages prior to 1810. [and,] List of officers of the Colonies on the Delaware and the Province of Pennsylvania, 1614-1776. Vol. 2 Vol. 2. [Harrisburg]: C.M. Busch, State printer of Pennsylvania.
It may be possible to confirm family relationships with Harman by comparing test results with other carriers of his Y-chromosome or his mother's mitochondrial DNA.
Y-chromosome DNA test-takers in his direct paternal line on WikiTree: