I would avoid brake cleaner around rubber seals or plastic parts, it dries them out. A mild degreaser would be a better choice.

Unless you're seeing drips on the garage floor, I wouldn't worry about it yet, you've just got "seepage". I had one side replaced at the dealership at about 205,00 miles and it was just under $300. My wife's 325i didn't get driven much one year, and both sides were replaced on hers at about 85,000 miles. It was $535.

2002 X5 3.0 242,000 miles
2004 325i 107,000 miles

Anytime I do clean it, it always gets back covered in oil like the pics. I have 2 small kids and we love to go for long drives so I'd rather not be left stranded somewhere or worse have it lock up on the highway

I was gonna use some dish soap in my foam cannon and my 1800psi pressure washer

I'm sure you're probably aware, but be careful where you point that high pressure nozzle. That's enough psi to easily force the soap solution right past the seal and into the differential housing.

2002 X5 3.0 242,000 miles
2004 325i 107,000 miles

+1.

Grease cutting dish soap, soft brush and garden hose would be better.

It turns out I just need my axel seals done. $400 Oem seals and bmw fluid

Always a good thing to save $150.

So 400 is good?

It depends if you don't want to get your hand dirty. The DIY is not that hard if you have three key tools. I did my a month ago and it took me 30 minutes. The most difficult part about it was getting up to apply the handbrake so that you can rotate the tire in order to get to all the bolts. The key tools are; a small crowbar to take out the old seals, 3/4 star socket (not 100% sure about the size at this time) and a Cup of the same diameter as the seal. I used one similar to the one on the second picture. As you can see from the first picture, you can replace both seals for less than $100 if you have the tools laying around in your tool kit or buy the tools and still save you a least $200. You don't need to take the tires off, leave them on. it is easier to turn them and be careful when taking out the old seals, don't scrape the inside of the differential with the crowbar.

I hope this help.