You can service the Bottle Jack

Why not a simple Bottle Jack?

Was checking prices on floor jacks and I noticed they have bottle jacks for way less money than the roll around lever-style floor jacks.

A 4 ton hydraulic bottle jack is $20 where as a 4 ton floor jack is close to $150. And you can service the bottle jack easily. There are ports to add oil and bleed it.

How many times will I be doing brakes and this little bottle jack will store inside my van (no jack when I got it) to boot.
 
A bottle jack will be adequate for this purpose, but certainly not the best tool for the job in my opinion. There are a lot of things you simply can't do with one, and therefore if you plan on working on your van in the future you would be well suited to a good floor jack.

I paid around $100 for my Torin Black Jack at Wal Mart and it has treated me well. I think it has a three ton capacity, why would you need a four-ton jack? Mine lifted the 5,000 lb front axle of my F350 just fine and is capable of lifting up to 19"

I also have a 4-ton bottle jack, and the one time I had to use it because my floor jack was out of commission really made me appreciate my floor jack!

A bottle jack is inconvenient in that you have to crawl under the truck to set it in place and jack it up, while a floor jack can easily be positioned from outside. they are also much better for low cars where there isn't room to place a bottle jack.
but a bottle jack has a much greater weight capacity for the price and size, and lifts straight up, whereas floor jacks tend to pull sideways when used on uneven ground.
as you know, neither jack is recommended for putting you under the vehicle, as a hydraulic failure can leave you crushed, so a good set of jackstands is recommended for any work that requires you to get under the vehicle. or safer yet is a broad stack of wood blocks under the axle(s) or tires. notice that if you have an entire axle in the air using a bottle jack, the vehicle will most likely fall sideways off the jack, but this is less common with a Floor Jack 3T. i've had the pleasure of telling bystanders that things really are ok after they hear a car fall off the jack, so i'm speaking from experience here.