I used to check the price of hire cars I was driving and surprise surprise Motorpoint would almost always have batches of that exact spec and at the sorts of mileages the cars are disposed of from the rental companies.
No coincidence.
As long as you know what you're buying it's not a problem. But there are some people who have hangups if they discover their car was an ex-rental *after* they buy it.
Quite hard to find out the "end user" rental outfit as they all seem to have a fairly bland finance company name on the V5 as the first owner.
They all get moved on before the first service is due though!