Post Office Avenue takes it name from the Post Office which relocated to the Musgrove Building in 1895 from the Old Town Hall. The Post Office was was on the first floor, rear south east corner with the entrance through the main center archway entrance on the Square down a long corridor. A rear entrance opened onto Post Office Ave. The Post office moved to Essex Street in 1917 and then to 71 Main St in 1931. We must note that when the Post Office was in the Old Town House, the new Barnard Street was sometimes called Post Office Ave. If a business location is noted prior to 1895 it most likely was on Barnard St.

This property was once owned by Samuel Needham and sold to John Flint Jr. on Mar. 13, 1828 for $3400 with buildings. John Flint, at that time, was a cabinet maker who had built his shop on the adjoining corner lot on Main St. and PO Ave in 1818. Flint sold this lot for $1800 with buildings to John Foster of Haverhill and Henry Burtt of Andover, "Harness maker" on Jan. 12, 1830. Foster & Burtt were business partners and are referred to as "Saddlers". The men took a loan of $1500 from the Trustees of Phillips Academy on Jan.12, 1830.

John Foster & Henry Burtt would later purchase the double house at 35-37 Elm St in October 1835, now the vacant lot east of the Free Church. John Foster and wife Sarah (Burtt) lived on the east side of the house and Henry Burtt, wife Abigail (Harding) on the west side.

John Foster, 4th was born July 23, 1802 son of John & Sarah (Burtt) Foster. Sarah (Burtt) Foster b. 1805.
Henry Burtt b. Feb. 1, 1807, son of Jedediah & Sarah Burtt. Henry married Abigail Harding b. 1803, who died Apr. 27, 1856. John Foster died at 47 years of age on Sept. 3, 1849. The 1850 Andover Valuation schedule lists Foster & Burtt - Dwelling house & Barn $1700, Work shop $425, Paint Shop, $350, 1 1/2 Land $200. Henry Burtt is assessed $1000. for Horses and Carriages. Sarah W. Foster, Adx. Farm stock $160, 18 R. R. shares $900. Henry listed his occupation as "Stabler"

June 4, 1853 Andover Advertiser - Saturday – Auction Sales – By T. C. Foster, Public Auction on Tuesday, the 21st day of June at 3 o’clock PM, the following real estate in the centre of the South Parish in Andover, near the Eagle Hotel: viz
One undivided half of a Harness and Paint Shop, formerly occupied by Foster & Burtt, with the land under, and adjoining the same, with the widow’s right of dower therein; said premises belonging to the estate of John Foster, late of Andover, Saddler, deceased.
Also will be sold at the same time, the remaining Half of the premises, belonging to Henry Burtt.
The sale will take place on the premises and the terms and conditions will be known at said time and place. Sarah Foster, Administrator, Henry Burtt

We know from the deeds that Henry Burtt was the highest bidder and retained the property. He did however sell his business as the following advertisement appeared in the paper.
May 28, 1853 Andover Advertiser – Advert. – New Harness Shop – The subscriber would respectfully inform the inhabitants of Andover and vicinity, that he has taken the Harness Shop connected with the South Parish Painting Establishment, on Main Street opposite Elm Street, where he will keep and make to order Harnesses and Collars, of all kinds and prices to suit purchases.
Harnesses and Carriages Cleansed, Oiled, and Repaired, also Trunks, Valises, Engine and Garden hose at short notice, and on most reasonable terms.
The subscriber hopes, by strict attention to his business and reasonable charges, to obtain a fair share of patronage. – M. H. Purcell

Henry Burtt, wife Abigail took a new loan from the Trustees of PA on. May 22, 1855
May 26, 1855 - New Stable - Henry Burtt – has moved to his new stable on Elm Square adjoining his Harness Shop and M. P. Millett’s store fronting the Eagle Hotel.

Henry would later buy out Sarah Foster's share of their home in 1865. Sarah died on Jan. 25, 1867. Henry & Hannah E. and had a daughter Mary W. Burtt who later inherited the property. Henry sold his shop on the Square to Sarah A. Bean on Feb. 9, 1881.and died a few two weeks later on Feb. 27, 1881. Hannah Burtt was taxed for property at 35 Elm in 1900, with house shed, and barn. Hannah died on Feb. 9, 1914.

AA - March 1, 1881 - p.2 - Henry Burtt's obit. - Died in Andover, Feb. 27th, of heart disease, Henry Burtt, aged 74 yrs 27 days. Mr. Burtt was a native and life long resident of this town. He learned his trade of Saddle & Harness maker of the late Samuel Needham, deceased, who occupied on that business at the same stand in Elm Square, which has since been occupied by Foster & Burtt, and by the deceased for harness making and a livery stable. The seventy-fourth anniversary of Mr. Burtt's birthday was celebrated Jan. 29, and the same evening he received a paralytic stroke, which undoubtedly hastened his death. He has left a widow and six sons and three daughters.

Tenants of the building;
8 Post Office Ave - The Andover Candy Store, (1976/83/90)
Academy Shoe Store (1936)
Academy Shoe Store, Reg Norton (1940)
Norton’s Shoe Repair (1956) - Reggie Norton cobbler

10 Post Office Ave. - Sole Amour, (2011-
Barre Nine Studio (2012) “raising the barre”
Hands in Motion (massage) (2011)
Beauty & Main (from Musgrove Bldg.) (2009-2011)
The Cupcake Place (2007-2009) (then to The Spa)
Sweet Mimi’s (2000-2005), then to 94 Main Street
Helen Thomas Simply Smashing “funky presents” (2001), then to 90 Main Street
Kinder Klothes (1999)
The Sassy Radish (1998) (from 48 Park, 1996)
Emerald Cottage (1994)
Roland Moore Guitar Studio (1966)