Used car advice, good deal?

Hello, these GM vehicles have a lot of issues with the Body control modules, they fail quite a bit I wouldn't be surprised if this one already had one or more modules replaced. Also, at 150k I would be wondering about the timing components, timing chains, guides, etc, has all that been replaced already? That's pretty high mileage for a GM. The list of TSBs (technical service bulletins) is very long as well. It looks nice, but knowing the issues these vehicles have, it's a lot of money if you end up having to put more into it.

Well, the older models do have less electronics and modules, and it also looks like this is push rod motor, so there are much less timing components than an overhead cam engine, just take it for a good long test drive, make sure the check engine light comes On for a few seconds when you turn the key on so you know the bulb hasn't been taken out, and pop the hood after your test drive while its running and listen for any abnormal noises, ticking from the valve cover areas, etc, and it runs smoothly. Check the oil level and the transmission fluid for any burnt smell. If it's all good, and you like it, go for it. You can also take a look underneath for rusted out parts of the frame, but this depends on what state you're buying it from, down south here they don't use a lot of salt on the roads, so we see less rusted out vehicles than up north, these are the things I would look for when going to buy a used vehicle. See if they will give you enough info to look it up on KBB.

I couldn't tell you what kind of issues it might end up with, anything can break. Im not going to reference any other websites but do a Google search "issues that might happen with a 2004 GMC Yukon with 150,000 miles" and it will come up with a list of the most common failures for that year and mileage. As for me, I wouldn't buy one, but the search will give you an idea, this is the beginning of the list.

So, this is a basic KBB value I searched for, it varies a bit depending on the options the vehicle has, such as entertainment systems, it looks to come with two different V8 engines a 4.8liter and a 5.3liter. But this is the KBB national average $4800-$5600, so 7500 is above average for sure, as for someone coming with you, that I'm not sure of. It would be best if you knew someone who actually works on vehicles to come with you, since they would notice things, others might miss. The Yukon's come in quite a few different models (2nd list below) there's even a couple models that come with a V8 6.0liter and a V8 8.1liter which is a huge engine. But it might be tough to get the seller to come down by $2k. This is the info I found on KBB's website.

I take it this is your first vehicle purchase. I would say yes negotiate in person after the test drive and take a good semi long test drive so you can hear how the engine sounds when it's up to full operating temperature. I would open the hood when it's running cold, so right after start up, and then after the test drive. Listen for any ticking or knocking noises.

When you sit at a stop sign, if there are any cylinder misfires occurring you will feel it in the steering wheel, little rough shaking feeling. Also turn on some electrical loads such as the A/C and headlight High Beams at the same time, when possible, watch the instrument cluster for any dimming or pulsing of the cluster lights.
Something else to notice is if you feel the brake pedal and steering wheel pulse when coming to a stop, indicating either the brake rotors are warped or there are some bad suspension/steering components. Check the tire tread for uneven wear, and if you can see the thickness of the brake pads, it looks like the vehicle has low profile rims so you should be able to see at least the outboard brake pads.
Just things I would look for and check when you go to look at it. And ask for receipts from all repairs if possible.

Yeah, just write down those things to watch for, as for the price it depends on how reasonable they want to be, you could show them the KBB value. But some people are reasonable, and some are not, so I don't really have an answer for that, unless you see that the tires tread is worn low, or the brake pads look thin. I'm sure your father will help you out.