My garage floor is the original slab poured in 1930 when the house was built. It slopes and has a couple peaks and valleys, but the table is dead level. Adjustable feet on the pedestals allow the table to be leveled on virtually any hard surface.
From my limited woodworking experience, the most important thing (as others have pointed out) is having flat, square boards to work with before any cutting is done. A pool table may look simply put together but there is a ton of engineering and precision that goes into a properly built table that will play perfectly and last a lifetime. I thoroughly enjoy building things and took great pride in building the custom table lights I've built but I don't think I would attempt to build my own table and I have access to a full blown woodworking shop with all the commercial grade machines needed to execute the build at a high level. I certainly wouldn't even entertain the notion without the proper tools to perform the job. You can work around the no joiner/planer (raw materials cost goes up in having someone else flatten/square your lumber) but having a saw that cuts straight some of the time is a non-starter. You need precise cuts every time without fail. Otherwise, you'll be spinning your wheels, frustrating the hell out of yourself and have an end product that isn't very good.
