Hi Shorton - and welcome!!
Your list is pretty good: tires, carbs, fuel tank, brakes, and wiring will all need attention and virtually for sure, all the rubber bits should be replaced (brake hoses and tires at a minimum). A lot of people find that the control cables (clutch for sure - but often the throttle as well) need replacement but these parts are easy to get and not expensive.
Get yourself a manual - you can download and print one for free and someone here will have the link to do that. You really can’t do much without a manual.
As well as the threads suggested above by TwoMany, another good idea would be to invest a few hours reading some of the “resurrection” threads and among the best are:
- “My 60th Birthday Present” by Mailman;
- “Stella” by DanielBlack;
- “Restoring a ‘76” by GeorgeOC.
These guys brought mid-70s XS650s back to life in just a few months and they methodically documented their work with good photos and well-written text. Also, they asked questions and got excellent advice and data from folks on the forum who really know their onions. The back and forth of the Q&A will be enormously helpful to you. By the way - all three of their bikes are candidates for the 2018 XS650 “pin-up girl” calendar - so this forum DOES lead to very pretty and reliably running bikes in fairly short order.
While you are reading, I’d keep a note pad handy as there are valuable nuggets of info sprinkled everywhere on where to buy parts etc. Also - if you need a part, be sure to TELL US - and you might be surprised to find that someone has just exactly that part and they’ll sell it cheap ...or actually GIVE it to you for the price of shipping.
As for how much money, I’ll bet you’ll have $5-800 in it or more before you’re done (including the purchase price) but you started really low ($150 for a complete bike in not too ugly shape...holy cow!!!). Having said that, you will have a super nice, unique and very cool motorcycle that will make eyeballs click wherever you go. The XS650is actually a very nice bike to ride. Not the fastest or the sharpest handling, but it can’t be beat for general booting around the countryside and it’s sound is unique and a total chick magnet.
Aside from asking questions and posting lots of pictures, you’re well on your way.
Looks like you’ve got yourself a ball game there!
Pete