I'm considering getting a 2.5 inch lift for my 06 Jeep Grand Cherokee Laredo...

1.) How much would 2.5 inch lift parts cost?
2.) What size tire could I fit without rub after a 2.5 lift?
3.) How much would I be looking at to have it professionaly installed?
4.) Anything I should be warned of?

Thanks, GCL06