TP hexagonal sandpit from bouncy happy people is good quality and took about an hour to assemble. Yes, longer than most but the timber is robust and can be painted and kept treated to look smarter than plastic.
The Wooden sandpit will provide years of fun.

The cover is useful to keep leaves, and cats etc ot and the liner is fully fitted. First stage of construction is in a separate blog.

I guess the hexagonal design is a practical way of using shorter timbers- the play area is certainly big enough for domestic use.