if there is a no deal , the effects obviously depend on how long it lasts until the govt / its successors cave in and sign up to whatever draft Barnier has up his sleeve.
In the meantime ...
I expect unemployment will rise, increasingly exponentially with time and having a knock-on effect on businesses those customers use.
MrsT managed an extra 2 million or so in about 3 years of her de-industrialisation policy - led by Minford, who has unfortunately risen from his coffin to walk among Brexiters.
Inflation will rise too, due to shortages
Meds including nuclear isotopes - the govt should be lynched if they don't have an adequate plan for these
Niche markets for the super-wealthy will be ok, e.g. customised luxury yachts.
Probably the luxury shops for the top 1-5 % will be ok,
maybe profits a bit lower as some highflyer customers emigrate or lose their jobs
Poundland & the most efficient of the very cheapest shops will remain, because people have to buy essentials somewhere
More highly processed junk food than ever in supermarkets, with less fresh fruit and less meat of high quality
Maybe 1 or 2 household name stores will go in both the cheaper end and mid-range food stores
e.g. one of Tesco / Sainsbo / Morrisons and either Waitrose or M&S
Of course, customers will cut right down on "discretionary / luxury" goods & services
( if people thought they were in squeezed middle before ... )
Lots of small businesses depending on such customers will go broke, e.g. hairdressers, nail places etc
So will smaller estate agents, as house prices crash
Some fast food places will disappear, as will some small chains selling electrical goods, electronics etc
Apple will be fine - they even have 2 stores in Venezuela