Probation is imposed as a conditional sentence at the discretion of the court. This means that the judge will decide at the time of your sentencing whether or not there are valid reasons to place you on probation rather than just impose fines and costs or impose a straight jail sentence.
The judge decides each case on a individual basis and you will be given a full opportunity to tell the judge anything that you want him to know and consider before he decides on and imposes your sentence. The judge will evaluate whether your offense and you individually are suitable and appropriate for placement on probation. You can not just pay more fines and costs as a way to avoid being placed on probation by the court.