The quick answer
If budget is the top priority and you're fine with a shorter lifespan, an above-ground pool wins. If you want something permanent-feeling and fast to install with a modern look, a container pool is the sweet spot. If you have a small yard and mainly want to cool off or do hydrotherapy, a plunge pool is ideal.
Cost
Above-ground pools are the cheapest to buy and install. Plunge pools sit in the middle. Container pools cost the most up front, but still less than a full custom in-ground build — and you save weeks of construction.
Remember to price the whole project, not just the pool: delivery, pad or base prep, pump/filter, heater, fencing, and any permits.
Installation & time
Above-ground pools can go up in a day or two on a level base. Container pools are placed on a prepared pad — often a long weekend once the pad and utilities are ready. Traditional in-ground pools take weeks; container pools are popular precisely because they avoid that.
Lifespan & resale
Steel-framed container pools are the most durable of the three and are relocatable, which is genuinely rare. Plunge pools are also long-lived. Budget above-ground pools have the shortest lifespan, especially soft-sided models.