1) What is a package: Our brother ahamid gave the answer in this thread. I am just quoting him directly from his post.
"Package-B" (165/70R14 tyres with no wheel cups, non-retractable side mirrors, simple keys w/o remote control, only 02 speakers, no vanity mirror, no restraining board in front passenger seat, back seat fixed, only available in base colors)
"Package-F" (165/70R14 tyres with wheel cups, retractable side mirrors, remote control key, 04 speakers, 01 vanity mirror, restraining board in front passenger seat, back seat adjustable, available in all colors)
"Package-U" (185/60R15 tyres with wheel cups, retractable side mirrors, remote control key with keyless entry, rpm meter, remote control trunk, 04 speakers, 02 vanity mirrors, climate control AC, leather cover seats, restraining board in front passenger seat, back seat adjustable, available in all colors)
"Package-I'LL" (185/60R15 tyres with wheel cups, retractable side mirrors, remote control key with keyless entry, FF fog lights, Leather lined steering wheel, rpm meter, remote control trunk, 04 speakers, 01 vanity mirrors, climate control AC, leather cover seats with division in backside of seat cover for holding magazine, restraining board in front passenger seat, back seat adjustable, available in all colors+special colors)
"Package-RS" (1.5L)
2) Grade mean the quality of car according to japanease export board. All the JDM cars which are imported have "grades" written on it's papers. Like grade 2.5, 3, 3.5, 4, 4.5 etc. Better the grade better is the car. The grade is decided on number of repaint pieces, accidents, mileage and inspection reviews.
The 33000 Mileage is a very common mileage in the vitz found here. Mostly this mileage is tempered. How can you believe that a car released in 2006 has 33000 mileage after 7 years? and almost all vitz? Have you seen the mileage on export certificate? Please ask the dealer from whom you are buying the car regarding genuine japanease papers. It should contain a certificate:

You can clearly see that this certificate has all the required information. It has all the reported inspections of the vehicle.
The final mileage is written on export certificate:

This certificate tells that the mileage was 96,500 in oct 2009 when the car was exported.
regards,