When considering a water birth, you need to consider both where you will be giving birth, and what accessories you need to obtain. You can have a water birth as part of a home birth, at a midwife led birthing centre or in some cases as part of a hospital delivery suite. Most midwife led birthing centres have at least one birthing pool available, although it is usually available on a first come first served basis, and some hospital delivery suites now include birthing pools and active birthing rooms, although these are more common is those hospitals which have been refurbished recently and again are on a first come first served basis.
If you are planning a home birth with a birthing pool, then it will always be available to you, but you will usually need to provide your own birthing pool and make your midwife aware that you are planning on using the birthing pool.
You have the choice whether to rent or buy your birthing pool. There are pros and cons to both choices. Renting is cheaper, but you cannot be certain when your baby will choose to arrive, so you may need a very long hire period. The birthing pool will also almost certainly have been used for other deliveries before you, and while it will have been cleaned and sanitised thoroughly this may be a factor for consideration. That said, if you choose to give birth at a birthing centre or hospital they will usually not allow you to bring your own birthing pool so theirs will have been used by many other women.
If you choose to buy a birthing pool, you will need to consider long term storage, but if you are planning to have multiple children and homebirth all of them it may be more cost effective than renting the birthing pool each time. In addition you know that the pool has only been used by you, and there is no ick factor to consider with reuse.
Whether you choose to rent or buy your birthing pool, you will need to store it with easy access for a number of weeks. It is advisable to have the birthing pool in place from the first date that a home birth is advisable, i.e. once your midwife is happy that you labour and birth at home and the birth would not be considered premature, you should have the birthing pool in your home and easily accessible, and have identified the best location to set up and fill it. The best location will depend on your home, but in general you should choose the room you feel most comfortable in, providing the floor in there is suitable to take the weight of the birthing pool, all of the water in it, yourself, your birthing partner and your midwife. You should also consider how easy it is to get water to that location to fill the pool, and to drain the pool afterwards.