Considering the rear cog, freewheel and lockring were close to $100 I'd rather not guess the total ticket!!!

This was posted on another forum i'm a member of, it sums it up nicely, though i did not write it:

this technique works best with a 5 speed suntour perfect freewheel(very common). instead of 2 chain whips which is actually pretty hard to pull off, use the chain on your bike and a chain-whip.
first take the freewheel that your going to separate on a wheel that fits on your bike. now tighten the bolts to hold your wheel in place than take the chain off off your front chain ring so the chain is sitting on the bottom bracket.
wrap the chain around the 1st or second gear cog so the chain is able to wrap over its self. this should immobilize the cogs from going any where if you do this right you can take the chain whip and put it on the outermost cog and start trying to unthread the cog(i find it easiest to use the frame and the handle of the chain whip and squeeze hard it takes alot of force to get the first one broken. then just unscrew the first two cogs and as stated before the rest of the cogs just slide off. this procedure works best for 120 spaced frames (but if steel you can always coldset) then you don't have to redish the wheel. when you thread the first 2 cogs back on just one will work if you want (i like 2) just hand tighten them for when you start pedaling you will tighten the cog on the more you pedal.

ok so, single speed and fixed gear are different, but the build is still the same-ish correct?
see i believe i got confused (sorry) cuz i want fixed gear

yeah, they are different in that a fixed gear is a true fixed gear. You pedal backwards, you go backwards. If the bike is moving, the pedals are spinning. No coasting.

A single speed means that is has one gear, but also a freewheel, so you can coast.

Builds are pretty much the same. Lots of fixed gear bikes will not have brakes. S/S bike NEED brakes.

I build up is the same-ish but different as well.

A dedicated fixed hub will require rebuilding of the rear wheel if you want to re-use your old rim. From a spacing perspective there's nothing you need to do, the chainline should be pre-set from the factory. If you acquire a 120mm hub you'll need to reset the rear dropouts to 120mm, if you acquire a 126mm hub your frames will be good to go. Another option is to buy a complete pre-built wheel.

The other fixed gear option is to locktight a fixed gear cog onto a conventional hub. This technique is less expensive and follows the same build instrcutions as a SS. I DO NOT agre with build technique. Im my opinion is a short cut. If your going to do it, do it right.

Do they make 126mm fixed hubs?

any formula hub will du you just need to add 3mm spacers or washers behind the lock nuts on each side