I have always had more than 1 project going, so have to work with a budget for each one.
Tires, nothing wrong with using tires that are not new, that are in good shape, close to the correct size, not putting alot of miles on them anyway.
Headliner, I used a new Walmart Blanket, about $20. It is already sewn for the bows every few inchs. Easy to install, looks as good, if not better than most headliners. Walmart.Com list a "micromink", I would like to see, and if nicer than what I have, I will install another headliner.
Muffler, I bought a $70 pipe bender, , about $60 for new straight pipes, and bent my pipes myself. Have a small mig welder. Have plenty of mufflers lying around from cars I have junked, and a couple of new mufflers new in t he box I bought at flea markets, but am running no muffler for awhile, just straight pipe...
If I was wealthy, I would still deal with my old cars on a budget, as I like the challenge. If I was wealthy, I would still would rather have my old Plymouths/Dodge than a $50,000 show rod. Our oldies have "character", as the people on this site. God Bless all of you guys..