I'm trying to place some figures within a document as well as some figures at the end of the document. Packages like
endfloat seem to force all figures to the end, but I would like some flexibility. How can I make LaTeX put some figures in the text and some at the end?
The short answer: As Barbara Beeton mentions in her comment, LaTeX preserves the order of figures (also called floats), so the short answer is to place all the figures you want at the end of your document, at the end of your document.
If some of the earlier figures cannot be placed, then they may also migrate to the end. This can be prevented by using the
\FloatBarrier command of the
placeins package. The standard classes do this internally to prevent figures from migrating into a new chapter.
All the gory details of figure (float) placement are described in Frank Mittelbach's comprehensive answer to this question: How to influence the position of float environments like figure and table in LaTeX?.