I am skilled LaTeX author. I authored several LaTeX packages.
I can write for you a document which contains complex mathematics, vector graphics (tikz or other), presentations or nontrivial LaTeX macros which redefine the default behavior (such as colorizing all math formulas in document).
The price is for 30 minutes of work. Ask first for estimate of the total cost of your document.
Plain TeX is also possible.
I can also fix your broken LaTeX file or suggest some improvements.