apexhunter
Ten Pointer
A suggestion to avoid some of the warping of the posts and the stringers is to shop for KDAT lumber (Kiln Dried After Treating) in no worse than a #2 grade. The higher grade (especially for the 4x4) and being dried will greatly reduce warping and twisting that most all 4x4 will do once installed. You will pay more but it is worth it to avoid excessive movement. For the fence pickets I would highly suggest going with #1 grade if the price doesn't bust yoru budget. #2 grade would work but the #1 with less defects will provide better longevity- these don't necessarily have to be KDAT as there is less movement in a board versus a post. The comment to use 4x6 for gates is very good- I'd bury these a tad deeper with full concrete backfill to provide the strength to withstand the weight and movement of a gate...and pay a bit more for stainless steel hardware as it will pay for itself in a few years.
Do not, repeat NOT use the prefab panels from a box store as these are typically made with lower grade, scant thickness material and are assembled with substandard fasteners. On the fasteners you can use ring shank nails or screws and while galvanized will last a good while stainless will least indefinitely (unless you are near the coast where everything will corrode eventually). Again this is dependent upon your budget. It is like the old Fram filter commercials- pay now or pay later.
Do not, repeat NOT use the prefab panels from a box store as these are typically made with lower grade, scant thickness material and are assembled with substandard fasteners. On the fasteners you can use ring shank nails or screws and while galvanized will last a good while stainless will least indefinitely (unless you are near the coast where everything will corrode eventually). Again this is dependent upon your budget. It is like the old Fram filter commercials- pay now or pay later.