save money for a flat deposit

This is an IMPOSSIBLE task :/ Where am I going to come up with £21,000 for a deposit on a 3 bed flat. Sob.

So I see my dream flat on the ESPC website, and this dream takes a very sharp turn into disasterville. Where can I get £21,000 for a deposit? :( If anyone would like to a) loan it to me; b) help me obtain this vast amount of money or c) give me the money as I’m freaking lovely, then please let me know asap and I’m sure we can get something organised.
Suddenly my savings account seems pitiful. Well, it is. Sob.
Damn ESPC for advertising a lovely flat…with 3 bedrooms…a living room…kitchen…bathroom…showerroom…boxroom…and a study…Damn their eyes. In freaking Marchmont/ Sciennes land…Gaaaaah.

Yes Mr. Rental agent, I hope to have enough money to put down the deposit on MY OWN flat in a few years. This is a pretty long term plan, but yes. It needs to be done. I’ve spent enough years giving people money for rent, gaaah.
I want to have my own bright pink bedroom in Edinburgh with photos plastered all over the wall and have parties without worrying about spilling wine on the white couch…because obviously I’ll have a more sensible coloured couch. Also, a gas hob, electric hobs are so slooooow.
And I’d like a pet.