Simplify jQuery validation
I'm not much of a jQuery freak, but I still have some points on this code. In your amountValidation function, you have some duplication and overhead:


if(errAmount == true)



can be written:

if(errAmount)


Also you always do the same thing when an error occurs, but that's in each statement:


if(errAmount == true){/* mark the field */};  
if(errGVAmount == true){ /* mark the exact same field */};
if(errNeedAmount == true { /* and yet the same thing again */ };



you can shorten this to:

if(errAmount || errGVAmount || errNeedAmount){ /*mark field*/ };




Your variable names could use some change too:

errAmount on the first look is like the geeneral error overall, not that amount is null / empty.
You could use errAmountNull instead.

errNeedAmount sounds like you have no amount given yet, which would be errAmount.
I would use errAmountTooSmall instead

Nobody knows, what the GV in errGVAmount stands for.
From the requirements I would call it: errAmountUnallowedValue