Don't worry Helen, clickable links don't really work on this forum because it uses an old format. I converted it for you.
The caravan in the advert is an Avondale, this company ceased trading last year so spare parts might be a problem.
Not every caravan has an oven, I noticed that the Avondale has burners and a grill so unless you were considering holding dinner parties or cooking the Sunday roast in the caravan you should be ok.
The main thing to look out for in any caravan is signs of damp or water ingress. Pay particular attention to the Avondale because they were known to suffer from hairline cracks in the front and rear grp panels which allowed water to enter causing damp.
Look in all of the corners, under bed boxes and at the walls inside lockers and lift the rubbers around the front windows slightly.
Any signs of soft spots, bubbles, black mould or the 'wallpaper' lifting is indicative of damp.
There are a few pointers
Here and a good browse around the Home Page of this website ( click on home page inside the blue box) will reveal more information.
If you click on the headings the links work on the home page. Make sure that you look at
Towing Law to ensure that your towing vehicle can tow a caravan safely and legally and to check the driving licence requirements.
If you have any more questions just ask.
Good luck