Well, one day they will set up shop!
Go by the service recommendations; small engine = not much oil in there (about a litre+ a bit?) = change it more frequently than big engines.
If you look back on earlier posts (you can search around using key words) you will see that some guys have seized their small capacity engines by running the oil "dry" (Look who's talking - I did the same thing many years ago with a 250cc!).
The filter will be small as well = smaller surface area.
The type of oil filter wrench I have is based on an expanding system of "prongs" that close more tightly on the filter as it is turned anti-clockwise; It is reversible for tightening the filter. Therefore it is universal and will grip a range of sizes of filter cans. There are other types as well - strap wrenches etc etc.
Have a good look at the engine for how you will access the filter (I usually need an extension on the spanner to reach in there) and drop it off the bike once it is un-screwed, and then get a wrench that will do just what you want.
ps I am assuming in all of this that the engine has a "can" type of filter!!