Parts on the bike I kept and still use:

Crank arms, 52t Chainring, Handlebars, Stem, BB, Headset, Frame, Fork, Seatpost, Seat, Toecages/straps

Paid 50 bucks for the bike originally so tally for all that is 50 bucks.

I overhauled the headset/BB myself and opted not to replace them. They're old, and probably heavier than newer components, but they still work just fine.

What I bought:

New Wheelset (200)
New Tires (60)
New Brake handle (10)
new Brake (20)
Tubes (had tubes already but [5])
Brake Cable/Housing (10 bucks)
Rear Cog (20)
LockRing (2)
Chain (15)
Pedals (25)
headset spacers (.5)
Bar tape (5)
Shorter Chainring bolts: (2)
Rim Tape: (2)

Total new Crap: 370-ish

Total Tally: 420 bucks

Wow... I guess that's a lot more than I remember spending.

Though to be fair...

Originally I rode the bike as a ghetto Singlespeed, meaning, I stripped off all the unneeded parts and just shortened the chain and chose the best gear on the 5speed freewheel for chainline. At that time, I also replaced the brake cabling and bought the housings. That's also when I overhauled the BB/Headset.

A year later I started having problems on the rims and had to replace them and decided to go the extra mile to make it a full fledged Fixed Gear

I did have access to tools when I did most of the rebuild but I bought these tools after I finished so I could tinker at home:

Chainring Bolt Wrench (5)
Combination Chainwhip/Lockring/15mm/14mm/bottleopener tool: (20) <-- Avenir brand, but has worked great so far
Small 15mm Axel nut wrench/tirelever (20)
Expandable wrench for working on headset (10)
Chain Tool: (10) <--- I have a multi-tool with Allen wrenches that had this, but I lost the bolt that pushes out the pin.
14t cog (10) < ---- bought this because I thought I wasn't going to have clearance for a 52 chainring on the inside of the spider, so I was Gonna run 42/14 instead of 52/18, but turns out I didn't need it. Was a temporary solution since it was an avenir cog, which I bound to fail.

That's another 75 bucks right there. Throw in an extra chain I bought when I was running 42/15, as wheel as a different set of tires from before the new wheels, and you're looking about about 550 dollars I paid, in full for conversion. From start to finish.

If you have access to tools, and didn't be a dope like me, and also if you shop around more, you could probably do my bike for more like 400 or less. but since my project was over two years and I made mistakes and bought things I didn't need (not to mention the tools), it cost me more.

I would say if you have the know how and shop around you could probably do my conversion for a lot less, especially if you have access to tools. My cost rose because of the learning process.

But I learned a lot about bikes/biking during the build so the extra hundred or two was worth it.