Do you mean central Warsaw? Or do you actually mean what is classed as Centrum ie the junction of Marsałkowska and Jerozolimskie? Either way, if you can find some empty land that is affordable to buy or rent just to turn into a car park I say good luck to you.
Nope hipi,there is a paring lot by UL Zgoda( where i stay) and is a existing parking lot but the owner is not brilliant and has only ground parking which is full always behind bank PKO,the bugger is not brilliant and wont rent cars wid foreign plates plus has no modern equipment to store cars(like 4 car high storage equipment etc.MY problem is I dont speak english...I read you will be in wawa till 13th ill be there wanna hook up? email me.