I have kept, cats, dogs, birds, fish, hamsters and snakes.
Currently we have a Ted the Greyhound, two birds, and two snakes; Oz the Corn snake and Bertie the baby boa.
Of all of these reptiles are both the easiest and the hardest. The advantage of the types of reptiles I keep is that they do not need to feed, often for weeks at a time, a big bowl of water can last several days.
Some reptiles are more difficult than others, please do you research, some of my vivariums are over two hundred cm by ninety cm. Not everyone can afford the space for these sizes of vivarium, and if your keeping lizards or some large pythons you will need to dedicate a large room.
The key to keeping them is to do your research. You need to give them the room they need. You need to know the temperature they need to be kept at and whether you need to change that temperature during the day and night and by season.
Often you need to provide a high ambient temperature, a hot spot and a cold area.
Next humidity. This can be a challenge, pick your vivarium carefully, glass, plastic and wood are your options. You also need to consider your substrate. Does it need to increase humidity or decrease it. Will it cause issue with feeding, does your reptile like to borrow?
Lighting, some want heat but not light, others need a UVB source, but also want to be able to hide from the light sometimes.
Lastly making the reptile feel safe; hides in the cold area and hot area is a minimum. Too much glass can make your pet feel exposed, does it need a dark area to hide in.
As I said, research is key. Choose the right pet and know your subject to give them a good life, and you can give each other years of pleasure.