Oh, Holgas can be so fun! Is this a plastic lens one? Don't be scared - it can be fun to not quite know what to expect. I haven't used mine in a while and if I remember correctly, it's zone focus and there are only two settings for 'sunny' or 'cloudy' (basically f/8 or f/11.) So expect to use it to shoot outdoors on sunny or slightly overcast days. Here's a shot on a sunny but foggy (lots of reflected light) day, so tricky lighting. Lots of silhouetting.
My second one had heavier vignetting than the first one, but they all have a bit of it at least. Here's an example of a heavier vignette (this was all the camera - I didn't add anything in post):
It can take a bit to get the hang of shooting in squares but it's easy enough to get the hang of it.
They tend to have the sharpest focus in the middle of the frame and then it softens as you get to the edge. That's partly what gives it that 'dreamy' sort of look. For example: Paramount 2 resized by limrodrigues, on Flickr
I also suggest using some gaffer's tape around the edges of the back while shooting. They're not designed for intentional light leaks, but it's still cheap plastic so it can't hurt to just seal those edges.
Been using a modified Holga 120N since last year, but sort of fall out of it after my vintage tripod broke. But found another tripod (mannequin stand) and Just ordered some Lomochrome 120 ISO: 100-400 for the upcoming fall travel.
I finally decided to use the Holga 120N that I been holding onto. I was impressed to see the results, I also did follow the instructions in the little booklet that said to tape up certain parts and so I did. Since these are just toy cameras, I expected them to be kinda crappy but I didn't expect this good of quality haha.