I am assuming the OP has good reasons for not wanting to move from where he currently lives (maybe where he is living is reasonable, rent-wise. Maybe he has good reasons for not wanting to move the kids to another location). Bearing that in mind...
Yes, as a cash buyer it is much easier to set yourself up as a company and have the company buy the apartment/house. You can't do it if you need a mortgage, as a bank won't lend to a company with no trading history. I'm not sure on the legals, but the company will still have to pay tax on any profits (rent) earned. You will have to pay tax on any remaining profits drawn down as dividend. That makes it sound like you're paying tax twice, and indeed you are, but any maintenance to the property (and probably a portion of other costs) should be deductible before profit, so you might be better off doing it through the company. You'll need an accountant to advise you on this though. Setting up as a company is easy enough and not expensive. It'd cost a couple of hundred quid.
The other advance would be that you would keep your eligibility for the help-to-buy scheme (I think! Again, get an accountant to confirm!) as a first time buyer. That's the only advantage to being a first time buyer nowadays, there's no exemptions to stamp duty.
If you're relying on any sort of means tested social welfare payment, the profits drawn down may have an effect on how much you can get. Whether it's a viable option will all depend on how much of your day-to-day costs you can write off against the rental profits.
Good luck and I hope things work out for you.