Re: Duich Lotts
There is no place called Dluich listed in the Ordnance Survey Name Books compiled in the mid-19th century. The consonants 'dl' do occu at the start of some Gaelic words, but I can't think of any other place names that start with 'dl'. However if a monoglot speaker of English were to pronounce it, the 'd' would come out something like 'g', and there were two crofts named Gluich in Islay, both now vanished. See https://maps.nls.uk/geo/explore/#zoom=16&lat=55.77978&lon=-6.19959&layers=5&b=1 and slide the blue button to the left to compare the map with the satellite view.
There are two references in the catalogue of the National Records of Scotland to plans of Islay including Dluich, but the map reference given for one of them (136792, 665434) corresponds to a place which is now called Ayen or Ayen Cottage https://www.geograph.org.uk/gridref/NR3665. The description of the other does not give a map reference, but it's likely to be the same place.
There are two listings of Duich in the Name Books for the parish of Kildalton. First the Duich River: "Applies to a River which forms the parish boundary between Kildalton Killarrow and Kilmeny. It takes the name of "Duich River" at Torra from thence it flows in a N.W. [North Westerly] direction, to where it joins the River Laggan about ¾ of a mile east from where the latter joins the sea at Laggan Bay. From its source to where it receives the name of "Duich River" it has various names in the different Localities in which it passes through". Second, Duich Lots (not Lotts): "A number of small holdings situate in the right of the road leading from Bowmore to Port Ellen, and about five miles from the former place. The property of John Ramsay Esqr Kildalton".
Duich Farm still exists. It is at https://www.geograph.org.uk/gridref/NR3154
Duich Lotts was definitely neither a town nor a single farm. Nor was it a hamlet, which is a cluster of houses close together, differentiated from a village by not having a church. It was a crofting township, where each house was sited separately on its own few acres of land.
It is quite common to find a dozen or so houses in the same area sharing a place name where a landowner had divided the land into smaller parcels and let them individually. This is what it looks like on the mid-19th century map https://maps.nls.uk/geo/explore/#zoom=15&lat=55.70832&lon=-6.25669&layers=5&b=1 - you can see the satellite view by moving the blue button to the left. Note that it is spelled Duich Lots on that map. There are some photographs at https://www.geograph.org.uk/gridref/NR3354 and https://www.geograph.org.uk/gridref/NR3353. Having seen those I am not surprised that it has been abandoned because it looks like wet boggy land and would have been very hard to farm.
A lot (or lott, if you prefer) is such a piece of land, which a crofter would have rented and on which he would have built a cottage (which means a simple building like the one here https://www.geograph.org.uk/gridref/NB3149 that would have housed the family and their livestock under one roof).
Allotments in this day and age are, very specifically, rented garden plots that are **not** beside the tenant's house, though in the 19th century the term was used for smallholdings. If there is planted ground next to and belonging to a house, it is called a garden. (For the avoidance of doubt, the distinction between a garden and a yard is that a yard is never cultivated. It may be unsurfaced but more often it is paved or cobbled or covered with tarmac or concrete.) Crofts would have a vegetable garden, and perhaps even a small flower garden, close to the house, and the rest of their land would have been arable or pasture.
Allotments in the contemporary sense are not common. There are estimated to be about 330,000 allotments in England and Wales, which works out at something in the region of one allotment per 200 people. In Scotland there are even fewer - about 10,000, which is about one for every 500 people.
As for Zoopla, it would not surprise me if the supposed house for sale there is a figment of the imagination of Zoopla's computer system, which hasn't even got the name right - it's added a comma betwen Duich and Lotts. Notice that all the financial figures are estimated, and there is no information about the supposed house, so the information is not based on an actual sale.