Welcome to the forum Bill
AS far as owning any Sunline, we all here feel they're the cat's meow. 99.9% of us feel they're best trailer ever made. That said, it depends how the previous owner took care of his/hers.
I have a 1985 T1350 known as a 13 footer and the Sunline brand is measured by its cabin/coach portion of the trailer. Other makers measure theirs from tongue to rear bumper (tip to tip).
When I bought mine it was in decent condition mechanically but I wanted mine perfect. I bought a lot of plastic fittings, roof vents, interior and exterior lights and other exterior pieces. I found most RV dealers carry all the components I needed, since 99% of those pieces are universal for all trailers. The only thing I can't find is a thermostat for our Atwood oven.
We even found wood paneling for an inside wall from Home Depot, the match was so close you'd have to look twice to notice the difference.
Sunline went out of business in 2006. and if you search our threads you'll see another thread where a few of us would like to see the Sunline brand brought back.
If you're a do-it-yourselfer you should have no problems with the maintenance. The older ANYTHING is the more walk-around checks you make just to know your trailer (or your car, or your house, or your boat).
The trailer you just bought is most likely the model I would seek next. We love ours but it's a tad too small. Great for my wife and I and for traveing long hauls but too small when we have the 4 grandkids .
There are many knowledgeable here to help you along the way.
Hope this helps
Jerry & Debbie
Ford Explorer 4.6 Triton V8, AWD, 4x4
1985 Sunline Saturn T-1350
Ham radio VE3JCJ, VHF, UHF and HF