Jojo, an Abyssinian guinea pig, was my first experience with this type of pet. He was a gift for my daughter, but I ultimately would end up caring for him. As a cat person, I never expected to enjoy rodents, let alone adore them. I admit, I initially was not pleased about taking over the care of this pet, but he quickly grew on me. That said, this is going to be a longer review, as guinea pigs are more complex than one would expect.
The first thing to know about guinea pigs are potential allergies. Most people that suffer from rodent allergies are allergic to a protein in the urine, so someone fine with cat dander may not do so well with a rodent. Making sure you and your family are free from guinea pig allergies before adopting this type of pet is a must.
Guinea pigs, also known as cavies, are social creatures. It is best to bond them with another guinea pig of the same gender if possible, especially if you will have limited time to handle them. Males will mount each other in displays of dominance as well as mark their surroundings by dragging their rumps on the ground. Two males can bond, but if you wish to have more than two, females may be a better option. Mounting, chasing, bickering and other displays of dominance are normal - but if the teeth start to loudly chatter - the cavies need to be separated. The scent from male territorial marking is quite unpleasant, so if that is going to be an issue, you might want to read reviews about female guinea pigs. Neutering a male cavy will NOT change his behaviors, only prevent reproduction. Do not attempt to house males with females. In addition to unwanted pregnancies, otherwise docile males will go to extremes and even fight to the death when it comes to "claiming" a female.
The cages sold at pet stores are generally not ideal for adult guinea pigs - a larger and more affordable C&C cage can be built with Coroplast (a type of plastic) and a cube organizer using instructions from the Internet. Clean up can be made a little cheaper and easier by using fleece instead of bedding. Droppings are swept up, and the bedding can be washed when the cage is cleaned. I have found cedar chips help combat the smell, but experts do not recommend it being the most healthy option for the cavy. Paper bedding is probably the way to go for disposable bedding. Make sure you have a place for your guinea pig to hide.
You may choose to bathe your guinea pig, as they can get quite smelly. Bathing can also help if you have mild local allergic reactions to the fur on your skin. Baby shampoo can work, but a small animal shampoo is recommended. Jojo used to get wood chips stuck inside of his rump from his territorial marking, and bath time is a great time to check over your cavvy for anything such as that out of the ordinary. They will also need their claws clipped from time to time.
Jojo enjoyed lap cuddles. Since guinea pigs tend to hate their fur being pet the wrong way, and the fur of an Abyssinian goes in many directions, I found the best way to pet him was stroking the little "mohawk" he had. If you want a guinea pig that you can easily pet from head to rump without potentially causing discomfort, consider a different breed.
Jojo had already been tamed by my daughter, so if considering this pet please realize a young guinea pig will probably be a bit on the wild side and need to be gently handled to fully tame. Young guinea pigs can't hold their bladders long, so have a towel handy! As they get older, they will learn ways to tell you they need to go back in their cage. Adult guinea pigs generally will not eliminate waste on a human unless it had been held too long - they will make noise or nibble a shirt before most bathroom accidents.
Guinea pigs need a constant and unlimited supply of Timothy hay. This helps them digest food and wear their teeth down, preventing overgrowth. Buying hay in bulk makes even high quality hay affordable on a budget. They will also need fresh fruits and vegetables - dandelion leaves from the yard are good too, so long as they are not exposed to pesticides. Guinea pigs also need plenty of vitamin C to prevent scurvy. Most pellet food is fortified with it, though adding bell peppers to their diet will ensure they get what they need. Guinea pigs make a cute "week week" noise when they beg for food. Jojo soon learned the sights and sounds of a human returning from grocery shopping and would "week" in response. Guinea pigs also have to eat some of their droppings to absorb all the nutrients. Even though it sounds gross, it is the equivalent of a cow chewing cud.
Some may say this is a great pet for kids, and while this is true in terms of personality, I think proper care is a bit high maintenance for children. They may also lose interest as they approach their tween and teen years. If parents do not mind doing some or all of the upkeep, I do think this is an ideal family pet.