It doesn't matter if you don't even have a garage (let alone a shop filled with a lot of different tools), you are still going to find that there are a lot of advantages to having a shop vac.
Don't Worry About Burning Your Old Vacuum Out
You may be concerned that using your vacuum like a wet/dry vacuum is going to shorten the life of the vacuum. The advantage of getting a shop vac is that it is going to help you to stop worrying about what you are sucking up.
Unless you have a machine that is made out of metal, you are going to need a shop vac to clean up big messes. Imagine trying to pick up a pile of nails or a bunch of drywall with a vacuum that is made primarily out of plastic. You will probably end up ruining the motor, and if you don't, you will definitely shred the belts.
Make It Blow
There are very few vacuum cleaners that are going to allow you to blow. Most are just intended to suck up messes. This can really come in handy when you are trying to get dust out of tight spaces that you can't get an attachment into.
Plus, if you have a porch or deck, instead of sweeping it up, you can just blow the dirt, dust and leaves off of it. A job that might have previously taken 10 minutes is now going to take less than a minute to do.
Keep A Spare In The Basement
If you have a furnished basement, you probably have to struggle getting your regular vacuum up and down the stairs. Now, you can keep your shop vacuum in the laundry room and you will be able to keep the area clean. If you are going to have a second vacuum, why not get one that is as versatile as a shop vacuum.
Throw Away Your Broom And Dust Pan
If you have a shop vacuum, you aren't going to have to even have a broom and a shop vacuum anymore. Wet and dry messes are going to be a piece of cake for a powerful vacuum cleaner.
Plus, you can just suck up all the messes that you would never want to clean by hand. The next time you see a bunch of dead bugs on your floor, you can suck them up instead of having to sweep them up.
Do Random Jobs
With some wet/dry vacuum cleaners, you are going to be able to do some jobs that you could only do with this type of vacuum.
For example, if you have a clogged drain, a burst of air going through the pipes might just clear it out. There are very few conventional vacuum cleaners that are going to be able to do that.
Another job that you can do with your wet vacuum is to clean out the swimming pool. If you aren't lucky enough to have a swimming pool, then you can clean out the gutters.
How about turning your vacuum into a leaf blower? If your yard isn't that big, it is going to definitely be possible.
The truth is, having just a cheap vacuum cleaner isn't going to cut it if you have a house and do most of the repairs and cleaning up yourself. Having a wet/dry vacuum is going to be an excellent investment.