What you see is what you get...they do have pics of the sprues on the Renedra site, you know.

Anyway, the problem with the mixed fence pack is that too many types are crammed into the same sprue. I got one set with the farmhouse. That's not enough to build a consistent fence around anything - barely enough for a small hut if you mix all types together. Then I bought an extra bag of two sprues at a show to beef it up. Now they're kind of usable but still slightly lacking. About six sprues would be needed to make a formidable set of each type. At that point you may have gone insane from all mould line trimming if you want to do it properly, though. Also, 2/3 of your work would have gone to basic bar and worm fencing. As stated before, scratch-building those from wood bits would probably be easier and look better. The single-piece worm fences don't even look entirely right when inspected closely.
Furthermore, there are gate pieces, collapsed bar fences and too many base pieces hogging space in the sprue. You won't need as many as you get when buying those six or so sprues to fence something properly. If the pieces were split over two sprues with proportionally more basic lengths and fewer details, it would be much easier to make reasonable sets.
The picket fencing, on the other hand, is well worth its price (obviously assuming that you need one). Scratch-building your own to the same precision is not exactly trivial.
So, trying to acquire and build all the three types at once is a large undertaking for one person. What you can do is to buy single type deals directly from Renedra. Alternatively, you could consider getting plenty and splitting them among several people, each making one type only. That would be more rewarding to everyone. (Although those cleaning up the two simpler types would still get a shorter stick in that deal...)
Interestingly, I didn't find the gravestone set that tempting. They seemed to suffer from typical problems of plastics - 2D details and slight softness. However, I can afford being picky as I already have piles of neat metal and resin stones from various sources. For a quick, cheap job from zero to playable that set should be fine. I just don't need one any more.