@deebouchie It's how I bought my place at the age of 27. Was already house-sharing to that point. So I simply bought continued to house-share for the next 5 years. However, after 5 years, after my last housemate moved out, I got some work done which dragged on and on and I began to get used to living on my own, and as I was now 32 I really started to want to live on my own so never went back to it.
The secret is to have the house-share mindset from Day 1 of buying the place. You are both housemates (it is just you who benefits financially). While you don't need to become BFF with the person you are letting the room to, it does need to be someone you enjoy (or at least tolerate) living with. If you are already used to living alone - don't do it. If you are going to have a mentality that "you have to put up with a stranger in your home" - don't do it. If you can't accept that your house/apartment is now this other person's "home" as well - don't do it. If you can't accept that your housemate is a person who will probably have slightly different habits/standards/hobbies/ideals to you - don't do it.
On the other hand - when advertising the room, do "vet" the person to make sure they are at least compatible with you and your lifestyle etc. i.e. don't just show them the room/house and be done with them - sit them down, have a chat (offer them tea/coffee/beer) and get to know a little about them (working hours/hobbies/social life etc). Even a 10-15 minute chat can tell a lot about whether you would get on living with a person or not. Every time I advertised, it did feel a little like speed dating, having a quick chat with 5-6 people over the course of 2-3 evenings before deciding on the "best fit".
Unfortunately, you will see people out there who are using the rent-a-room scheme but are absolute "horrible cunts" towards their "lodger" (they can only stay certain nights/no guests/expected to be out of the home most of the day and expected to be in their bedroom when they are at home. Not only should those people be kicked out of the scheme, but they should also get a slap.