You need more than one animal, they are herd creatures. Get mental problems if alone. Act weird. Not sure how much of a pet they will be for you. All the cameloids I have met are more standoffish than affectionate. Can be nice, but not like cows or other farm animals. Just very different thinkers. You can't hurry them, ever. We thought about them, decided not to purchase.

Have a plan on how they will be sheared yearly. Hair needs to come off for healthy skin. Do you know any spinners or spin wool yourself? Locally, owners feed wormer regularly to both Alpaca and Llama. Some daily, to prevent the brainworms our local Whitetail deer pass along as they run thru the pastures. If worming is not kept up, Alpaca and Llama will die younger than they need to. Llama and Alpaca need regular hoof care if you are not on a mountain to keep hoof worn down. You or someone else must provide that hoof care.

A gelded male or two, might be your best choices. Ungelded males might be more dominant, harder to handle. Females are more expensive. Not always easy to get bred, if you are thinking babies.

Local Alpaca owner has only had a few babies, 1-2 a year, with his 6 females and male kept together. Has changed the male a couple times, females too, trying for better rates. Still low births. Biggest year was 3 cria. Babies are fragile, die easily.

He keeps a flock of gelded males, just for the shearing. Breeding is a sideline now, with his wool production from the geldings. His are nice animals, but watchful, rather than friendly, despite much kindly handling. He likes them, works with them a lot, because they can be very spooky to manage. He hauls them to exhibit at town festivals, Fairs, trying to grow interest in wearing the wool products they can produce. Helps that Alpaca are so CUUTE! Lovely eyes.

You might just put an ad in the local paper, try to locate some. Around here the Llama are cheap or free. There has to be some overstock of Alpaca too. They are pretty common now. Finding a breeder, you may be able to get geldings of poor color, cheaply to a good home. Or not, because some folks have inflated values on the animals. Trying to get their money back out of them. They are not as valuable now, as they used to be when rare.

Alpacas are herd animals and hence need to be kept in a group. They NEED a guard animal. Donkeys and llamas work well for this.
Alpacas are not pack animals, meaning they are not built to carry loads or to pull carts. They are raised for their wool.

The big economic problem is that importation of alpacas was made nearly impossible, which in turn made them more scarce and supply demand curve raised the price. This was very good for the people who had alpaca's early on, but since with alpacas you are buying in to the scheme and then selling your work it can be harder to turn a profit and with something like a Llama where you are buying someone elses work then selling yours. Or it can be easier, it depends on whether or not a sucker comes along and really wants to buy in.

Alpacas can pack a light load, just like almost all medium and large sized animals, if you are into hiking there is nothing wrong with throwing a 40 lb pack on the back of a well trained alpaca, but I wouldn't recommend hooking them up to a heavy cart or loading them heavily like you might a much larger Llama.