Many people first start noticing scooters when they are looking for ways to maximize the economy and convenience of commuting to and from work.
Aside from the obvious savings associated with fuel, tolls and parking with a scooter, leaving your car at home can also have long term benefits, both from a mental and convenience standpoint. If you are a one car family (or want to be) taking a scooter to work can free up the family cage for your S.O. at a fraction of the cost of a second car.
Some people also notice that they are much less stressed (read, nicer to be around), after a commute on two wheels, since they find the ride invigorating and the traffic less restrictive.
But as to the question of whether scooter commuting is right for you? A lot will obviously have to do with the weather and road conditions where you live/work, and how you personally weigh the relative merits of convenience, comfort and economy.
For instance, if you are the type who takes the car to the end of the driveway to fetch the mail when it's cold or raining out, commuting on two wheels might not be for you. But if you enjoy the outdoors and are comfortable in a reasonable range of temperatures, scooter commuting might be a good fit.
However, an important point to make before we go any further is that if you are very new to riding, it might be a good idea to take a season or two to become confident / proficient in a wide range of conditions before committing to daily commuting on two wheels. Simply put, don't expect that commuting will immediately give you the experience and skills you'll need to stay safe.
Just as with commuting in a car, on a scooter you will have to deal with daily pressure to arrive on time, avoid hazards on the road, and steer clear of poor/aggressive drivers. But if you also have to contend with your own limited riding skills, something is likely to give; meaning chances are good that, best case scenario, you will arrive late... or worst case scenario, you'll end up having (or causing) a crash.
A good MSF course will give you the basic tools to become a competent rider. But honing those tools in a variety of conditions over the course of a riding season or two is an important step before committing to a regular commute on two wheels.
What is a reasonable commuting distance?
There is no hard and fast rule as to what is considered a reasonable distance to commute on a scooter. Shorter commutes of a few miles/kilometers are obviously attractive candidates. But several MVers can attest to comfortably commuting 45 minutes or more each way.
What you are riding and your own physical condition will have a lot to do with how far you can comfortably ride every day.
But a rule of thumb is that the longer the commute, the better and bigger the scooter needs to be to do the job.
What scooter is best for commuting ?
Daily commuting will place a mechanical strain on any vehicle, and cheap / bargain scooters simply will not hold up to daily use.
Assuming one of the reasons you are considering commuting by scooter is the financial benefit, if your scoot starts falling apart and spending increasing amounts of time in the care of your mechanic... there goes your plan for an inexpensive commute.
Also, the longer your daily commute, the more likely it is that you will want a scooter capable of traveling at highways speeds. You may not actually need to get on the highway, but fast secondary roads will still require you to be able to easily maintain 50 - 60 Mph (80 - 100 Kph), day after day, without taxing the reasonable capabilities of your scooter.
So for a 15 minute commute on side roads, a 150cc scooter might be fine. But for a longer commute, and/or one that requires highway time, 200 - 250cc is a reasonable minimum to consider.
Even a quality scooter will feel the strain of daily commuting, so plan on doing scheduled service slightly before the recommended mileage, and check fluids and tire pressures obsessively.
It is worth taking into account the wear and tear on you, as well. A comfortable scooter with sufficient power to keep up with (and if necessary pass) traffic can mean the difference between arriving relaxed and arriving stressed.
Although this forum is called 'Modern Vespa', you've probably already noticed that MV members ride a wide range of scooters from various manufacturers and eras. That said, the Modern Vespa is an extremely robustly built (some would say 'overbuilt') scooter which, with proper care and regular service, can easily stand up to the strain of daily commuting.
But when you get into the larger scooters and engine sizes in the market place, you needn't limit yourself to just Vespas. Look and ask around.
I won't go into the issue of 'All The Gear All The Time' here. The amount and level of armored protection (Helmet, jacket, pants, gloves, boots...), you decide to wear is a personal choice. But keep in mind that, statistically speaking, daily commuting will place you in harms way considerably more often than just using your scoot for the occasional weekend joy ride... so choose wisely.
It is always a good idea to have reflective piping and stickers on whatever jackets/gear you are wearing; especially if there is even the smallest possibility that some of your commuting time will be in the early morning hours or after sundown.
An aftermarket horn is a must if you will be commuting. Pedestrians barely hear the OEM horns on most scooters, so they are next to useless in terms of alerting drivers of your presence. Ask around and install a horn that will keep the drivers around you in their lanes.
You can also assume that once in a while a nail or screw will find your tire... usually after dark when it's raining. So have a good flat repair kit (sticky strings, mushrooms, spray goop... whatever works for you). Just make sure you practice using it before the need arises.
One of those LED headlamps, an adjustable wrench and a decent Multi-tool should also live somewhere on your scoot.
Having one of those roll up reflective vests stowed under the seat is also a good idea in case you break down, so you'll be seen on the side of the road.
A good battery operated flashing LED light (you can find them at bicycle shops) is a good thing to keep under your seat since most scooters don't come equipped with four way hazard flashers. If you have to stop on the side of the road... you will be happy for the extra visibility.
If you have room for it, a first aid kit is a nice thing to have under the seat or in the top case. But you'll want to have realistic expectations of what kinds of things you might really need while on the road. Bandages, anti-biotic ointment, blister patches, tweezers, finger splint, tape, allergy, headache and upset stomach meds: Absolutely! Neck brace, leg splint, portable defibrillator and sterile surgical kit: Not necessary.
A charged cell phone goes without saying, but even more important; the number of a 24 hour motorcycle rescue/flatbed service on a sticker inside your glove box will come in handy at some point. Trust me.
BTW, while we're on the subject of charged cell phones, if your scooter doesn't have a 12V outlet for charging phones and other gadgets... have one installed. You won't regret it.
Recommended clothing and gear
Even if you are lucky enough to live in an area where year round riding is possible, you will soon discover that into every commute a little rain must fall. So be prepared.
At a minimum, you will want to have some decent rain pants and a good waterproof windbreaker that will fit over your riding jacket.
Don't believe the weather reports. Keep your rain gear in a stuff sack under your seat or in your top case. Nothing is worse than hearing the patter of rain on the office windows at lunch time even though the pretty weather girl on the morning news assured you it would be sunny all day.
If you plan on riding in the early spring, late fall and any part of winter, you will need some good layers, a cold weather riding jacket, and a neck warmer. While not an absolute necessity, a waterproof insulated lap blanket/apron (e.g. Scooter Skirt or Termoscud) can make a frigid commute downright pleasant.
If you will be riding any distances in a hot climate during the summer, consider getting a camelback or similar system since some helmets make drinking from a bottle or cup awkward, at best.
Most scooters have underseat storage and perhaps a glove box. If you want more space, a top case will offer storage for gear and the convenience of being able to stop off at the store on the way to or from work.
Just keep in mind the list of gear that needs to live safely on your scooter at all times. You'll quickly learn to prioritize and toss the extraneous stuff back into the garage where it belongs.
One of the downsides of having a nice scooter for your commute is that inevitably someone will want to take it from you. And the sad truth is that there is no thief-proof way to secure your scooter; at home or at work. If someone really wants your scooter, they will have it.
With that in mind, selecting a scooter with a decent immobilizer, buying (and using), a well rated lock and chain, parking in well lit, high traffic areas, etc. are all necessary steps you'll need to take to improve the chances that your scooter will still be there when you go out to get on it.
Thieves are mostly a lazy bunch (otherwise they'd be commuting to work like you!). Anything you can do to increase the Pain In The @ss factor associated with stealing your scooter may convince the thief to move on and look for an easier mark.
But in the end, the most important security tool in your arsenal against thieves is a decent insurance policy with a full replacement rider.