Its very difficult to re-align a car with lowering springs.You'll more than likely have to buy camber kits.
rather than getting lowering springs, check out adjustable coilovers. these can give you the ability to raise and lower the car to some degree but the extra freedoms that you get make them much better. with lowering springs you increase spring rate and lower ride height to a very specific setting. if you are not happy with the results you are S.O.L. with adjustable coilovers though, you can change the damping settings (compression and rebound), some of the spring rate, height and ultimately you can fine tune your cars ability to roll in corners. this means that if you want a nice comfy ride for every day driving, you can raise the car and soften the ride for comfort. then on the weekend when you want to hoon around, you can lower and stiffen the settings to let you do whatever you want. once you find a good balance you can get a car that is comfortable as well as sporty which is something that lowering springs won't give you.
sadly, coilovers car more expensive than lowering springs but I think they are worth it considering you get more options in ride height and other settings. if you had bought numerous sets of springs to attempt to match the adaptability of coilovers, you would end up paying a lot more and still not get all the features that coilovers give.
also, if you don't really care as much about looks and just want performance, anti roll bars maintain the comfort and usability of your stock ride height but reduce the car's tendency to roll making it more sporty. they are very cheap and can be installed quickly. they just don't lower the car. (for the most part, unless you go to tracks, lowering a car won't do much for performance, what helps is a stiffer suspension that manages the cars eight better)
Save your original stuff or no one will buy it when you sicken of the results of your folly.
As your question it is not possible to express theoretically. So you should make contacts with any auto repair shop or car repair experts. Here you can't get the perfect solutions for your car. How ever if you belong to the Tampa city then you can met a repair shop as Tire Mania Auto Repair where you can get solution for your car. If you want to know more can visit the site like tiremania.net.
cut a half coil off the springs you have and see how that works for you. Eibach are quality spring that isn't too expensive.
Ok, so I want to lower my car, it's a ford fiesta 2010 model.
I was wondering what would be the best springs and stuff to use that arnt overly expensive.
I want decent springs that are going to last ages and be reliable.
I'm a hoon so they will have to be tough lol