Apologies for the *very* verbose post and long list of pictures, however the car has a long list of issues and I wanted to seek the advice of those familiar with Volvos. Any advice is appreciated.

The car is not mine, however it is a kinsman's (original owner) whom I am helping. It is a first generation MY2004 S40 with the B4204T4 and Aisin AW55-50 sold in the North American market. It has ~140k miles.
It has been used primarily for city driving and short trips at that. I estimate that the car has had ~30-50k cold starts in its lifetime. ~3-5mi average trip. Always garaged. Serviced regularly by mileage, not age. Car still driven regularly.
The car had a *really* bad idle, dangerous intermittent hesitations, a suspension clunk in the front right, and mushy brakes. Browsing through service records and speaking with the owner revealed recent issues with oil and coolant.
Apparently, since ~90-100k miles through present, each time the car was taken to a Volvo specialist for its regular service (~5k mile OCI), the technician noted that there was barely a quart of oil left. Long history of electrical gremlins.
And in the past year or so, the car had a leaking heater core, which the owner remedied with K-Seal and refilled with 3 parts concentrated universal Prestone green coolant to 1 part tap water.
The timing belt was serviced as part of the 105k mi service in 05/2017. Ignition coils were replaced soon thereafter, and struts were replaced around 65-70k miles.

It had the following codes pulled at the local parts store:
P0172: System Rich (Bank 1)
P0101: MAF Circuit Range/Performance
P0130: O2 Circuit Bank 1, Sensor 1
P0139: O2 Circuit Slow Response Bank 1, Sensor 2
P0172: System Rich (Bank 1)
P0101: MAF Circuit Range/Performance
P0130: O2 Circuit Bank 1, Sensor 1
P0139: O2 Circuit Slow Response Bank 1, Sensor 2
P0301: Cylinder 1 Misfire
P0304: Cylinder 4 Misfire

Following is the current list of *known/suspected* issues, what I've done, if anything, and what I believe was the cause. I have pictures of most, but not all. I've diagnosed all of this myself and recognize I may have gotten some things wrong.
1. Rough idle. There are many issues that could be causing this, though it has improved greatly. Can't believe it idled at all with all the idle issues.
2. Clogged air filter. Owner was following 30k mile or longer change interval. SoCal is dusty, and it was really dirty. Helped improve performance significantly.
3. Bad MAF. Tried cleaning; no change. Tested part, and confirmed bad. Replaced with new OEM MAF from VDO/Continental. Improved things further, cranked over better.
4. Leaking Fuel Pressure Regulator (FPR) and torn vacuum hose. Haven't replaced, fuel coming out of hole in vacuum line.
5. *Green* (Yes, green) brake fluid. Copper contamination? Green dye? Tech filled with coolant? Don't honestly know, but want to flush and bleed with fresh DOT-4. Brakes are mushy, but not quite bad enough for me to think it's the master cylinder.
6. Bad front right strut mount. Struts are ~70k miles old. Thinking entire struts should be rebuilt around old springs, but money's tight. Bad idea to just replace mounts? Can see movement when bouncing car up and down. Hasn't ruined tires yet.
7. Drooping headliner. Was badly glued (not by me). Don't care. Interior lights burned out. Don't care. Other miscellaneous electrical oddities. Don't care.
8. Clogged PCV. Fails glove test instantly. Smoke from dipstick and tailpipe. Advised to leave dipstick loose/up to relieve pressure, but damage has been done.
9. Cam seal leak or leaks. Bad. Losing lots of oil. Suspect was caused by PCV. Running low on oil and hot from running out of coolant due to former heater core leak couldn't have helped.
10. Oil soaked timing belt. Caused by cam seal leak(s).
11. Cracked oil cap gasket and dirty oil cap. PCV, heat, and age, I'd assume. Smell gas in the oil fill. PCV, I assume.
12. Deteriorated rubber and plastic; lots of it. Oil, gas, and heat. Timing cover is deteriorating. Timing belt, ignition coil wiring harness, and hoses too. And who knows what else.
13. Split insulation and exposed wire on ignition coil wiring. Also, oil made it through the gasket on the plug for the wires next to the timing belt. Cleaned out the connector, but the gasket was destroyed.
14. Upper coolant hose leaking.
15. Maybe a dirty IAC? Don't know.
16. Fouled plugs? Probably. Runs very rich. Always smells like gas. Maybe ignition coils or just wires. 1 and 4 misfire makes me think its related to the two plugs per coil design linking 1 and 4, 2 and 3. Switched the coils and will pull codes again.
17. Hose going from IAC(?) to intercooler outlet(?) before throttle body was completely split. Soaked in oil. It's now being held together with a Velcro zip-tie and a cardboard shim. Did at same time as cleaning ignition wiring connector. Greatly improved idle. Don't know which was responsible, but assumed as this certainly was a huge vacuum leak.
18. Oil in hose before throttle body. Fairly good river. Assume this is contributing to smoke from tail pipe. Caused by turbo? PCV?
19. Dirty throttle body. Gee, wonder why.
20. Coolant(?) leak from turbo? Seals in turbo bad maybe?
21. Broken quick-disconnect clip for the fuel return(?) line for the fuel pressure regulator. Doubt this is important.
22. Needs coolant flushed and replaced coolant looks dirty even though new, and incorrect.
23. Power steering ATF just below/at min. Top off with Aisin ATF.
24. Compression? Haven't tested. Seems OK, but don't know.

I have no idea how many more things may be wrong. I may have forgotten to list a few, the list is so long. Am I incorrect in what I'm thinking on any of this? Are there any suggestions of things I should try? The owner believes that they cannot find a better car for what this one's worth (Worth 0 IMO), does not have money for a new car, and it's obviously not economic to have this taken care of at a garage. How much would this likely cost at a Volvo specialist @$100/hr labor rate? How many hours of work would it likely take to fix all this at home best/worst case scenario? Parts from FCP Euro, etc, obviously varies depending on what route is taken in replacing parts and how much is replaced. But I know it's not going to be 0.

Again, sorry for the long post. Any suggestions or advice would be very much appreciated (e.g. Set the car on fire, sell it, keep an extinguisher in it, do an engine flush, don't do an engine flush, replace with an updated part, replace the turbo, rebuild the turbo, idiosyncrasies with the '04MY, anything at all.).

Cheers


Top of engine with covers removed. Ignition Coils out for testing.

Torn FPR vacuum line.

Fuel rail, FPR & vacuum line, quick-disconnect.

IAC, and visible below is broken IAC hose(?)

IAC hose(?) broken.

Dirty oil cap and visibly cracked gasket.

Dirty connector, oily timing belt.

Dirty oil fill.

Fuel line seems to be rubbing slightly.

Off-center strut mount. Deteriorated.

GREEN?!

Exposed wire.

Ignition coils and negative wire colors.

Intercooler outlet(?)

Throttle body closed.

Throttle body open.

Oil going into hose of before throttle body.

Oil coming out of hose before throttle body.

IAC hose(?) split.

Coolant leak(?) from turbo?

 

Sorry for double-posting. Didn't mean to. Don't know how to remove this duplicate thread.

 

What is a 2004 Volvo worth in your country , here in good condition its around 2000 us but in that condition probably 500 so that must be considered before spending , probably sell for spares