(a) On motion filed within 30 days from entry of judgment, a new trial may be granted for the following grounds:
(1) Irregularity in the proceedings of the court, jury or prevailing party, or any order of court, or abuse of discretion, by which the party was prevented from having a fair trial.
(2) Misconduct of the jury or prevailing party.
(3) Accident or surprise, which ordinary prudence could not have guarded against.
(4) Excessive or inadequate damages.
(5) Error in the assessment of the amount of recovery, whether too large or too small where the action is upon a contract or for the injury or detention of property.
(6) The verdict or decision is not sustained by the great preponderance of the evidence or is contrary to law.
(7) Newly discovered evidence, material for the party applying, which he could not, with reasonable diligence, have discovered and produced at the trial.
(8) Error of law occurring at the trial and properly preserved by the party making the application.
(b) The court, in granting new trials, may allow the same upon the payment of such costs by party applying therefor, as the justice and equity of the case may require, taking into consideration the causes which may make such new trial necessary.