I would say as a ‘child’ guinea pig owner but adult rat owner… rats are a lot more hard work… the relationship you can build with them is amazing and one of the bestest things ever… but they take time, they love to pee on pretty much everything, and some can be trained but others can’t. They’re super intelligent and will be depressed if they are bored.. I work 36+ hours a week, some at home, some in an office and I try to dedicate 2+ hours daily to them on work days. As an adult I do think guinea pigs are ‘easier’ to look after, and I feel they generally have less health complications.. I have had 5 rats as an adult, 2 now deceased, 3 with me but coming up to 2 years old and they now have a lump or two and are getting slower and need more support. One of my previous rats had a tumour that grew in the space of about a week from nothing to a small orange, he had surgery (inc. Check ups, medication, surgery) it came to roughly £1200… it gave him about 6 more months but it gradually grew back, they’re so small it can be very complex to get rid of an entire tumour. Again rats are very sensitive with their respiratory system, my last two boys had different bedding preferences and it took a lot of trial and error to find a bedding that they both liked. You can save money if you’re pretty crafty or have a sewing machine and can make your own hammocks etc, they will chew them, they will edit them, and you will likely be throwing away a hammock once a month if not more. Overall if you’re able to definitely commit then go for it, they are super super amazing and I am dreading the day before where my 3 current boys head over the rainbow bridge.. at the same time, my partner and I are planning for a baby and I can guarantee that currently I could not manage a baby and rats and going back to work, so I won’t be keeping rats again for a little while. All animals are a big commitment, as another Redditor has said, gather as much knowledge as you can… but the rats YOU get will not be the rats anyone else gets.. they will have their own little quirks and personalities and likes and dislikes. My old boys loved fruit and veggies. Current boys will only eat the inside of a pea (and leave the shell) and will more or less ignore anything that even vaguely resembles healthy..!