Irrigation System...

I'll just start by explaining my situation.
I live in rented accommodation, and unfortunately the garden is almost pure clay, and turns into a bog over winter. As it's rented, I could be made to leave any year, and as such, I'm not spending money sorting out the poor garden. So everything, and I mean everything I have are in pots. This however makes watering a nightmare, and expensive. I have around 50 pots! Good thing is, if I had to move, they can all come with me.

I want to set up an irrigation system. I've watched Thomson & Morgan's guide, and also went to a local garden centre to price up what I need. Didn't seem too bad price wise.

So what I'm asking is, number one - anywhere you would recommend to buy what I need? Online, or in the North West...
And number two - any advice on setting it up?

Thank you.