You can do diff cases (axles) and xfer case yourself. Very easy on almost any truck. Diff cases you will need a gasket or you can use RTV, up to you. Xfer case you simply unbolt, drain, and fill up. My rover has single fill and drain bolts for the diff cases though, so it's super easy compared to the Jeeps. But it has other glitches that make up for it, aluminum engine block that does NOT like heat.....lol
I might pay them to do the power steering though, it can be a pain to bleed, and you definitely do not want air in the line. Might be worth 85 bucks.
Me personally, I would hold off on the axles and xfer case though, unless you took in some deep water/mud, and do the transmission fluid instead, possibly a coolant flush also.
I would rank tranny and coolant fluid (flushes and refill on both) more important than axle and xfer case gear oil for sure @ 30k miles. Esp if your on road mostly.