Clutch pedal feels really hard

The original clutch started to feel really hard to press, jumpy but it always engaged. The dealer recommended to replace it. After replacing the original clutch at the dealer, the clutch has never been the same.
The new clutch still was hard to press down. Took it back to the dealer and they replace everything but the pressure plate. Clutch was still feeling hard. Took it back and the dealer said he did not know what else to do!
I started to ask mechanics and other people what the problem could be. Most of them said the pressure plate. After feeling totally frustrated and with pain in my leg while driving in city traffic everyday, I decided to install a new clutch kit.I paid $700.00 + for this job. The clutch still feels the same or worse! They also flushed the slave(the clutch fluid). Please help!