Change ToC Level of ToC, LoF, and LoT

Question

I'd like my front matter (ToC, LoF, LoT) to show within my ToC on the same level as sections (as opposed to chapters)...

MWE:

\documentclass[]{scrbook}

\KOMAoptions{twoside=false}

\usepackage{tocbibind}

\addtokomafont{partentrypagenumber}{\nullfont}
\addtokomafont{chapterentrypagenumber}{\mdseries}       

\usepackage{tocstyle}
    \usetocstyle{allwithdot}
    \settocstylefeature[-1]{leaders}{\hfill}
    \settocstylefeature[-1]{pagenumberhook}{\nullfont}

\usetocstyle{KOMAlike}
    \usetocstyle{allwithdot}
    \settocstylefeature[-1]{leaders}{\hfill}
    \settocstylefeature[-1]{pagenumberhook}{\nullfont}
\renewcommand*{\addparttocentry}[2]{%
    \addtocentrydefault{part}{\partname\nobreakspace #1}{#2}%
    }%

\begin{document}

\frontmatter

\part*{Front Matter}
    \addcontentsline{toc}{part}{Front Matter}

\tableofcontents
\listoftables
\listoffigures

\mainmatter

\part*{Report}
    \addcontentsline{toc}{part}{Report}

\chapter{Chapter 1}
    \section{Section 1}
    \section{Section 2}
    \section{Section 3}

\appendix

\part*{Appendices}
    \addcontentsline{toc}{part}{Appendices}

\chapter{Appendix 1}
    \section{Appendix Section 1}
    \section{Appendix Section 2}
    \section{Appendix Section 3}

\end{document}

Answer 1

First of all I would remove packages tocbibind and tocstyle and the \addcontentsline statements from your MWE:

\documentclass[
  twoside=false,
  listof=totoc,% add a tocentry for lists like LOF and LOT
  toc=chapterentrywithdots% dots as line filler for chapter entries in TOC
]{scrbook}
\setuptoc{toc}{totoc}% add a tocentry for TOC

\DeclareTOCStyleEntry[
  dynnumwidth,% adjust the space for part numbers in TOC as needed
  entrynumberformat=\partnumberwithprefix,% part number with prefix
  pagenumberformat=\gobble% remove page number of part entries in TOC
]{tocline}{part}
\newcommand\partnumberwithprefix[1]{\partname\nobreakspace#1}
\newcommand\gobble[1]{}

\addtokomafont{chapterentrypagenumber}{\mdseries}
\begin{document}
\frontmatter
\addpart{Front Matter}
\tableofcontents
\listoftables
\listoffigures

\mainmatter
\addpart{Report}
\chapter{Chapter 1}
    \section{Section 1}
    \section{Section 2}
    \section{Section 3}

\appendix
\addpart{Appendices}
\chapter{Appendix 1}
    \section{Appendix Section 1}
    \section{Appendix Section 2}
    \section{Appendix Section 3}
\end{document}

Result:

---

If TOC, LOF and LOT should be sections instead chapters you could use lists=leveldown and \setuptoc{toc}{leveldown}:

\documentclass[
  twoside=false,
  listof=totoc,
  listof=leveldown,% <- added
  toc=chapterentrywithdots
]{scrbook}
\setuptoc{toc}{totoc,leveldown}% <- changed

\DeclareTOCStyleEntry[
  dynnumwidth,
  entrynumberformat=\partnumberwithprefix,
  pagenumberformat=\gobble
]{tocline}{part}
\newcommand\partnumberwithprefix[1]{\partname\nobreakspace#1}
\newcommand\gobble[1]{}

\addtokomafont{chapterentrypagenumber}{\mdseries}
\begin{document}
\frontmatter
\addpart{Front Matter}
\tableofcontents
\listoftables
\listoffigures

\mainmatter
\addpart{Report}
\chapter{Chapter 1}
    \section{Section 1}
    \section{Section 2}
    \section{Section 3}

\appendix
\addpart{Appendices}
\chapter{Appendix 1}
    \section{Appendix Section 1}
    \section{Appendix Section 2}
    \section{Appendix Section 3}
\end{document}

Result:

---

But if you really want that TOC, LOF and LOT are still chapters but get TOC entries like sections, then you could add

\BeforeTOCHead{%
    \renewcommand\addchaptertocentry[2]
        {\addtocentrydefault{section}{#1}{#2}}%
}

to the first example.

Code:

\documentclass[
  twoside=false,
  listof=totoc,
  toc=chapterentrywithdots
]{scrbook}
\setuptoc{toc}{totoc}

\BeforeTOCHead{%
    \renewcommand\addchaptertocentry[2]
        {\addtocentrydefault{section}{#1}{#2}}%
}

\DeclareTOCStyleEntry[
  dynnumwidth,
  entrynumberformat=\partnumberwithprefix,
  pagenumberformat=\gobble
]{tocline}{part}
\newcommand\partnumberwithprefix[1]{\partname\nobreakspace#1}
\newcommand\gobble[1]{}

\addtokomafont{chapterentrypagenumber}{\mdseries}
\begin{document}
\frontmatter
\addpart{Front Matter}
\tableofcontents
\listoftables
\listoffigures

\mainmatter
\addpart{Report}
\chapter{Chapter 1}
    \section{Section 1}
    \section{Section 2}
    \section{Section 3}

\appendix
\addpart{Appendices}
\chapter{Appendix 1}
    \section{Appendix Section 1}
    \section{Appendix Section 2}
    \section{Appendix Section 3}
\end{document}