Without offending anyone, after looking at the price of the wood, bolt/lag screws, time, gas, transportation, etc., it seems like the decent tables sold along the highway, or even at the big box stores, are good deals. The other issue is where the table will be used. In a covered area, or on a slab, or on the ground, all effect the longevity of the table. I have had both treated wood and cedar tables, and the treated wood ones last longer, wherever the table was located. All of my tables required a spring maintenance of tightening the bolts and checking structural integrity, but the cedar table often required a staining and sometimes a board replacement. I was given a redwood table once, and although it was still in good appearance after a couple years of use, the wood was very dry and brittle. From that I expected that most, if not all, tables do require some routine preservative coating, again depending on the climate conditions of the area. Guess I have this problem, I like tables to last a very long time and get the most out of the precious wood and my money, instead of just getting a new table every couple of years.
Good luck with making one for your neighbor. I did that 35 years ago. Was very proud of my work and the neighbor liked, but then made statements; "it sure is heavy", or "would it look better with a redwood stain", or "can it be modified for an umbrella". So, I don't make tables for neighbors anymore, but I do help them make their own.
