Placenta encapsulation can certainly be a DIY thing, and there are lots of resources/recipes/instructions out there (be careful though, some are NOT so good, or safe). One bonus to hiring a professional is that they can do it quickly, and return your pills or other remedies to you in a timely manner- ideally by the 3rd day postpartum, before your own hormones crash. You could certainly prepare your pills yourself, but many moms are just getting out of hospital at 2-3 days postpartum, and are trying to adapt to the needs of a new baby, breastfeeding, sleep deprivation, engorgement, etc. Professionals also know what they're doing, and more importantly, the WHY of certain methods (raw versus traditional chinese medicine methods, approaches to safety, when additional steps to preparation may be needed depending on the mother's birth or the handling/storage of the placenta at the hospital, etc). Placenta medicines are also very energy-based (especially in TCM), and a positive, respectful attitude is needed to make effective remedies- you don't necessarily want your husband/mother/friend preparing your remedies if they're going to be feeling disgusted/squeamish/grossed-out by your placenta, if that makes sense.
Depending on your area, placenta encapsulation can seem expensive. But consider the amount of money you may have spent on your wedding, your baby's nursery, etc. Your health is of paramount importance, and deserves priority too. Many mothers end up spending money on products and services that they might not have needed if they had consumed their placenta (regarding emotional health/breastfeeding support or drugs, supplements, etc). And honestly, the benefits of increased energy, better sleep, reduced bleeding, earlier and enhanced breastmilk production, and most notably- absence of the baby blues and depression that mothers who consume their placentas report makes it a very worthwhile investment. Quite a few placenta services providers offer payment plans, a sliding scale, or bartering- you can always ask.