1) You'll outgrow that in a week.
2) That's not going to help you do squats.
I was in the same position. I was cleaning the barbell over my head for squats, and decided that it was dangerous, and I couldn't increase the weight safely. Therefore, I was only ever going to squat as much as I could OHP, and it was never going to be safe. So I looked for a bench with a squat stand, and eventually came to the conclusion that a squat stand is barely any safer than just cleaning the bar. I've now got a power rack, bench and weights arriving tomorrow
Seriously, if you want to do anything but bench press, a bench-press bench isn't going to be enough. And if you want to start body building, 30kg isn't going to be enough.
It's a harsh truth, but you need to spend a lot more than £50. My Rack, Lat pully, Bench and 100kg oly weights cost me £695 including delivery - not that much when you consider the cost and inconvenience of going to a gymn for two years.