Hello Rick and Katy
We are glad to have you join us here and we look forward to reading of your adventures and experiences. Congratulations on your new to you rig. I am sure you will enjoy the website and forums. Good luck, stay safe and keep us posted.
Although many units of this age can have leaking hydraulics, it is all about how well these systems have been maintained and/or abused. You will want to clean the effected areas with a de-greaser so you can then operate the system and find where the leaks are actually at. One top off the reservoir when all the slide outs are in and the jacks are up. Level the unit and while they are down lubricate the shafts with some automatic transmission fluid (Dextron III). Now, look for any leaks. If the seals at the jack are leaking Operate them a few times as the seals may have just be dry and/or dirty causing them to leak. Sometimes getting them clean and lubricated will stop these type leaks but not always. The other leaks (hoses or pump assembly) will have to be dealt with on as as needed bases. Let us know what you find.
The leveling system should be down in normal cases but the room can be operated most of the time when the coach is not quite level. It is important though that the coach is level to operate the refrigerator for any length of time.