Then the probate at the end states: that his estate "at the Time of his death did not amount in value to one Hundred Pounds".
There are two questions here:
1) how his money/lands came to be lost. He was the last member of his family to be able to live as a 'gentleman' from his small lands. His son who inherited the properties had even more debts at his death 20 years later, and the lands disappear from the family altogether.
2) what sort of income he would have had with 200 acres of around 70% arable, 20% pasture and 10% meadow. I have found one article which estimates that land in Merionethshire was worth about £0.46 per acre per year in 1820. I know this was one of the poorest counties of North Wales.
Income derived purely from agriculture can't be guaranteed. It's dependant on so many factors, weather, disease, market prices, cost & availability of labour, servicing debt, government policy, war & peace, world conditions &c.
The article "Causes of Discontent and Distress" I mentioned in my reply #2 gives indications of some problems with which famers had to contend in early 19thC.
War with France began 1793 and lasted for more than 20 years. As in WW1 and WW2, Britain had to produce more food. More land was enclosed to enable famers to increase production. Price of grain rose. As well as food there was need for leather to make soldiers' boots and saddles for cavalry and materials for their uniforms, e.g. linen (from flax), wool. Inflation was high during the war.
End of the war brought falls in grain prices. Then there was a series of bad harvests. Farmers had spent money extending their farms and improving land to meet demand. Some may have taken on debt.
It's possible that Mr Jones lost his entire 1816 harvest and his hay crop. Choice would have been between buying scarce hay at a high price to feed his animals through winter, selling more animals than usual in autumn at a lower price than in previous years because so many other farmers would have been selling too, or keeping them and risking their deterioration and perhaps death. His son would have inherited the same set of problems. Your ancestor would have been paying 5% interest on his debt.
Mr Jones would also have been contributing to the parish poor relief. Local recipients may have been swelled by some of the thousands of discharged soldiers unable to find work to support their families.
Introduction of the Corn Laws was intended to protect British corn production if price of corn fell below a set level.
There are books and articles about agriculture in this period. Try your public library if you live in Britain.
Another source is local newspapers if they existed at the time. Browsing adverts and articles may help fill in background. Also national newspapers for the situation generally. There may be agricultural journals from the period.
Have you found tithe records for the property?
