The courts require double your fines as bond in the appeals process. This is outside of the $30 per charge filing fee. It's ridiculous.
I'm sorry I'm being vague about the situation. It's taxing on the mind and the family to actually have to consider weighing right and wrong and have to base your decision on finances.
They don't always require a bond twice the fine for the appeal.
As others have said, your next step is a trial de novo.
http://www.moga.mo.gov/statutes/C400-499/4790000200.HTM . The cost for this is only $30 and it is automatic assuming you file it within 10 days. I believe this is calendar days. This is assuming it was tried by a judge, not a jury. It's like you get to redo your trial without the town's own judge being involved.
If you were to lose that, you would be filing an appeal through the court of appeals. The cost of that is $70 and you will need to have the state make a transcript of your trial, which depending on the number of pages, will be about $150 for a trial like yours. After that, the only real costs are making copies -pages and pages of copies- of everything you file to the court and postage.
The appeal to the Missouri Court of Appeals will have to be based on errors made in the lower court. Simply trying to argue your case or point of view will get your appeal tossed in a summary judgement. In addition, you have to be sure to contest the errors made in the lower court at the first reasonable time. This means either before or during trial. If you forget to object to inadmissible evidence by the city when they submit it into evidence, don't even bother with it in your appeal; The CoA will not address it 99.5% of the time. It's called preserving the errors for appeal. After the next trial, if you were to lose, you would also make a motion for retrial based on any and all errors you might consider in your appeal. The judge will most likely rule against your motion (because he is not going to admit he was wrong), but this will be essential for your appeal to the CoA.
Even if you have objected to an error, filed a motion for retrial, filed a timely appeal, filed all the required documents for your appeal, perfected your appeal to meet all of the court's requirements (font size, colors or paper, format, citations, index, etc.), and the appeals court finds the lower court made an error, it still doesn't mean your conviction will be overturned. It the error is minor, and the CoA figures you would have been found guilty regardless of the error, you will lose the appeal. Also, if that error is significant, the court may remand the case back to the lower to court to redo it. Instructions will be given about the error and how evidence may or may not be used in the new trial.
I would at least do the trial de novo. Be sure to file a motion to dismiss before trial though stating Constitutional reasons why the charge should be dropped. Make the city do some work and not just get the cop up on the stand to lie. In my experience, city prosecutors of towns don't like to do all of that and normally assume they can just show up to court and come up with some reason on the fly. Sometimes they just think since it's the local judge they work with all of the time, he will accept it; sometimes he is right. Other times, I've had judge toss the case because the PA didn't have his legal argument ready and presented to the court, on paper. Being in trial de novo, he won't be working with his buddy judge, and will be more in a real court setting and not "kangaroo court". The judge at this level may very well toss the case if the PA doesn't respond to your motion to dismiss.
Whatever you choose, best of luck. If you have more questions about the appeal process, you can PM me; I have some useful documents.