The dealer is going to charge you at least $100 per hour for labor plus shop supplies is always put in to about 5%? of the cost (usually shop supplies is a fixed fee based on some % of total cost) to cover cost of clean up and oil disposal fees.
Then you have the transportation cost to get the tractor to the dealer. You can easily triple or more the cost of oil and filters rather than do it yourself. Even if you have to buy the used oil container and tools to remove the filter and any drain plugs, it will be much less to do it yourself.
Engine oil change is a 15 minute job at most, at least after you get the oil filter off that has been installed at the factory by a 1000 pound gorilla. Be sure to have a good set of filter pliers to get it off. Look at the drain plug or plugs (many 4 wheel drive units will have 2, one on each side of the front drive shaft). My LS required a hex wrench of about 18mm IIRC, in any case much larger than anything I had so I had to find something to fit it before completing the oil change. The oil filter was a real beatch to get off also and I almost destroyed my filter wrench getting it off. Most folks complain about the same problem with super tight filters so be aware of that.
When changing the HST filter, remove the fill cap and insert a shop vacuum hose in the hole to put a vacuum on the reservoir, then you should loose much oil during the swap of filters. IF you don't do this, oil is going to be pouring out of the reservoir until you get the new filter installed.
Still even with all the potential issues, it is a rewarding experience and insightful gains into your tractors workings to do the service yourself.
You should check the front axle oil level as many have found it to be low after running it for a while.
