Apparently, a nominal 29-foot trailer with BunkHouse and SSlideout, per the brochure.
The Slideout and Slideout wall can become a big deal if there has been water intrusion and the wood is weakened or rotted. Post pictures and description.
Winterizing is very straightforward. You can do it in a couple of ways. Regardless of which way you choose, you MUST always turn the bypass valves on the water heater and then drain it by removing the drain plug accessed via the outside door. The drain might be a simple plug or a plug with an "anode rod" attached. (Our 2002 has a drain plug with a petcock in the plug, but it's a very uncommon brand of water heater.) You will also drain the fresh water tank, black tank, and gray tank.
- You can drain the plumbing by opening the low point drains and the taps to let the system drain.
- You can get a fitting that couples your air compressor to the "city water" inlet and blow the system clear by opening one tap at a time until air comes out.
- You can fill the system with RV antifreeze (NOT automotive antifreeze!) by using the trailer's water pump. This is my preferred method. Get two gallons of RV antifreeze (Walmart, around $3 per gallon). Near the water pump will be a two-position selector valve with three pipes/tubes. One goes to the fresh water tank, one goes to the trailer's plumbing, and the third goes to a short piece of tubing. Turn the selector valve so it points to the short tubing. Put the tubing in the bottle of antifreeze. Turn the pump on. (It will run for a several seconds and stop.) Go to each tap in turn and run it until the flow is solid pink. Then go to the "city water" inlet, remove the hose (if any) and the little domed screen. Stand aside from the inlet and gently press the stem in the inlet until pink fluid comes out.
Water heaters are easy to fix and most parts are inexpensive. But there are several varieties. Please open the outside door and get the manufacturer name and model number to eliminate confusion. Report them here. For example, it might be a Suburban SW6DE.