Round pools are much easier than oval pools.  Cheap pools usually have fewer parts to assemble than better pools, but the parts generally fit together better on the better pools.

It helps if the directions were written by someone who spoke English as his or her native tongue.  If you can get an assembly DVD, so much the better.  Some things are easier to watch in real life than to figure from words.

Ground preparation is by far the most important part of installation.  Take your time, and get it right.  We’re not talking brain surgery here, just the patience to keep digging up that ground until it really is level.  Even using a hand level, you could still be out of level by an inch across 24 feet and never see it until the pool is full.  However, the water is going to be perfectly level, and that one inch mistake will be very apparent.  Consider hiring a tractor operator to level your ground and dig the trench for your electrical work.  It will be the best money you ever spent.

The actual pool assembly is fairly easy, and best done with only two or three people.  With too many people, you tend to lose control of the situation, and steps get missed.  At two steps, wall erection and liner placement, it’s nice to have three to five people.  Most important, absolutely don’t open the first beer until the liner’s in.  I know of an egg-shaped pool where the help got too drunk too early!

If you hire out the installation, look for an installer that carries liability insurance.  If they do not carry Workmen’s Compensation (most installers do not), make sure your homeowner’ insurance will cover you.  Actually, unless you check that every plumber, carpenter, electrician, tow truck driver, pizza delivery person, chimney sweep, etc., doesn’t also carry Workmen’s, you should have already made sure your homeowner’s insurance covers you.

You’re interviewing the store by shopping.  Don’t be afraid to interview the installer.  Is this a part-time job, or a full-time profession?  How many adults are going to be on the job?  How much experience do they have?  If you’re looking for some unusual work or modifications, are they telling you what you want to hear, or are they willing to lose a job that’s not done right?

Be prepared for delays (a common problem) and overruns (a much less common problem).  You are hiring a contractor for outdoor work – subject to the vagaries of weather and seasonal help.  If you absolutely have to have your pool installed by the graduation party, and you receive an estimated date for three days before the party, life does not work that way.  It won’t happen.  If you don’t care when it goes in, it will be early.

Back to the original question, if you’re reasonably handy (change your own oil, spark plugs or muffler; hang sheetrock or wallpaper; do minor electrical work) you’ll find pool installation pretty easy.  There is, however, not a prayer that you’ll get the liner in without wrinkles.  Even the best professional installers get wrinkles once in a while.