I have driven commercially in different cities and different situations for over 25 years.
How much you make can vary greatly depending on the amount of business for that town and the individual company’s method of compensation. When I started out the company I worked for paid us a percentage of what we made, and that percentage also could fluctuate depending on different things- full time / part time… season of the year etc. - because there were competing companies and it was important that drivers tried to sell rides for their own income and company. This added a huge level of stress to the job for me and created a lot of animosity on the street between drivers of the different companies… BUT it also allowed me to make more money than average because I was pretty good at selling rides. So for me- dealing with the stress of the competition was the biggest drawback. If you work in a one company town, or one where fares are arranged by a street manager or a first in, first out system- that is much more relaxing.
Now that I have my own carriage company, do mostly special events which are booked in advance and work in a small town with no competition- I don’t think I would relish to having to go back and do that again.
The next thing that I would list as a downside is dealing with impatient drivers or road ragers and/or verbal abuse from people on the street (men) You are out in the open, exposed and vulnerable and you can’t leave fast- so if a creep wants to, they can match pace- and it’s not like you can duck into a building to get away from them. Some of it was pretty harmless and non-threatening just typical construction worker type cat calling type stuff- but when it’s your job to be outside all day it would really wear on me as it added up. (PS- It’s been a few years since I’ve been cat-called 
) Really scary incidents with people on the street were very few and far between.
I have not had to deal much with animal rights activists- but it’s becoming more and more of a problem all over the country- so that can also be a big stress.
There are several traffic tactics that can help reduce the level of difficulty of driving in an urban area with cars. Most of the tips have to do with understanding that the flow of cars in a city is like a bloodstream in an animal - it has a pulse. If you use the lights BEHIND you- they will do most of the work for you. I try to drive in a way that I never have to ask a car driver to yield to me and it’s possible to do that almost all of the time. Communicating with other carriage drivers when driving in groups is also very helpful- (sharing the road with another SMV driver who is an idiot could be listed in the job drawbacks.)
Typical example- line of carriages is in the left lane of a one-way two lane street. Traffic is able to flow past in the open lane. There is car blocking the carriage lane with flashers on, and only the first carriage can see it ahead. They maneuver to the right lane to go around it and the car traffic which was in the right lane now has to slow. The line of slowed cars is going to prevent the other carriages from being able change lanes- and now the car traffic backs up the length of the block so all he remaining carriages are boxed in by slowed cars, and all the cars are boxed in by carriages. UGLY dumb situation. Instead the driver of the first carriage needs to communicate a “get over” signal to the LAST carriage in the line. When the last carriage is able to change lanes- the whole line can execute a beautiful synchronized lane change like a drill team.
The upsides of the job are countless but he’s the top of my list-
#1 the partnership with your horse.
#2 the ambassador role between horse/carriage and the modern family/ kids.
#3 It’s the coolest job ever right?
#4 Working outside
One last thing I’ll suggest you do before you start Batman- Is to go check out the other companies in that city before you develop any allegiances. Talk to the other drivers and really get a feel for the overall picture. I have worked for the best company in the country, and I have also worked in a situation I wish I could forget ever happened- once you get connected to a horse, or to a person on a personal level- it’s hard to leave for another company… so do your homework first.
