Most everyone in the Alpaca business are in it for the fun, and the profit. But in the occasion you just want to have an alpaca as a pet, thats not a problem!
Which ever way you want to take your alpaca business is up to you, but investing is going to be involved with both. You can still make something by just having them as pets by selling their fleece/fiber. But your not going to make a living, and rarely a profit, depending on how many alpaca pets you plan on getting or have, and the quality of their fiber.
I personally just enjoy having my alpacas as pets, and every year they get sheared and I sell the fleece/fiber, which covers for some of the feed bill.
If you want to own alpacas just as pets, start looks around at farms in your area that might have package deals when you buy a couple fiber boys. I looked at 13 different alpaca farms before I found farm that was reasonable in cost, had a good attitude about selling them, their farm was clean and they said that anytime I had a question to just call them up and ask, make sure the farm you buy your alpacas from will 'stay' connected and with you for your first months or even a year and help you out along your adventures with alpacas.
If you never plan on breeding your fiber boys, I strongly recommend gelding them. It will keep them calmer and friendlier, you wont have any fights between them, which could result in injury, even if you geld them you should still cut their teeth to prevent injury in any play they may have.
For profiting with your alpacas, your going to need to find a nice farm that has quality breeding animals. Again, look around, it took me 13 farms just to find nice fiber boys, so for breeding quality it could take even more, that is - depending on how many farms are in your area. Always negotiate when buying and possibly setup package deals with farms if they dont already have one for buying multiple females, or buying a pregnant mother with a cria and so on. The more you buy the cheaper they get!