As there are no title deeds in the collection, it is not clear how the Wilsons came to possess their Belvoir estate, except for Ballycullen and Coolycasey. On 26 September 1712, Richard Wilson Junior was given a fee farm grant of these lands, 507 acres, by Henry O'Brien, Earl of Thomond [LE6/B/491]. By the time of Griffith's 'General Evaluation of rateable property in Ireland', 1856, David J Wilson held land in the following townlands: Ballycullen and Coolycasey, parish of Kilfinaghta, barony of Bunratty Lower; Ballyvorgal Bel, Belvoir and Belvoir Demesne, parish of Clonlea; Crag, Drumminakela and Snaty Wilson, parish of Kilseily, barony of Tulla Lower. In 1876 the estate was just over 3,000 acres with a rateable valuation of £1,056. Belvoir House was burnt down in 1881. John and Fanny Wilson made the remaining wing of Belvoir their permanent home in the 1890s. Many letters are addressed to John Wilson Lynch at Belvoir.
There were a number of mortgages secured on the Belvoir estate. The Presentation Nuns of Galway held a mortgage of £6,000 dated 14 May 1855, which they assigned to Hannah Fair and her sister Jane C Lambert on 24 July 1906. On 19 June 1862 a mortgage of £7,060 was registered against the estate following a judgement obtained in court by Patrick M Lynch. On 2 May 1862 David J Wilson mortgaged the lands of Belvoir in fee to Patrick M Lynch, for £6,000, subject to certain clauses of redemption. This mortgage was assigned to Arthur Ussher on 21 May 1877. The 2 mortgages held by the Fair family and the representatives of Arthur Ussher were paid off out of the proceeds of the sale of the estate in 1922.