I would say if you can go for a folding camper over a trailer tent they do offer that extra level of comfort we have found over the years they have become a natural progressive upgrade from tents.
definitely check out your cars towing capacity and you will be surprised that you prob can tow a combined weight of 3500kg as already mentioned. the biggest units being like our the Pathfinder is a braked trailer and will last you a lifetime. I would also say , if your budget allows, go for the newer fabrics acrylic after around 2009 for the Pennine units or make sure the previous owner has not waterproof treated any canvas units you look at.
you can pick up some great priced Pennine Fiestas, sterlings Pullmans Pathfinders and Countryman units on the free classified sites like preloved Facebook marketplace and others.
i would also suggest if you can fund one the sunncamp airvolution trailer tent. they have a blow up full front awning and only weigh in around 500kg to sleep 4 plus with under bed pods.
Thanks for the advice all. I've gone for a Conway cruiser. It's a 94 model part way through a do-up job so has had a new ISH canvas, bed boards and upholstery. Down side was I couldn't check electrics but wiring looked in good condition and gas pipe needs fitting to check cooker. Comes with new pod for under the unit and skirt but doesn't have an awening but can look to get one next year. My main worry at present is if I can even move the unit on my drive/garage given its on a slope and the unit weight is 750kg. The increase in size gives me a 5cm clearance into the garage! Eek
Congrats dude! If I had seen this thread earlier, I would have advised a Conway or Pennine. I was in your shoes a few years ago, and I'm firmly of the opinion the 95 Conway Countryman was the best 650 I've ever spent or will spend.
In my experience, the Conways are very easy both to maintain and modify to your exact needs. Don't be afraid to experiment!
If you're new to towing, there aren't many pitfalls. The key is to keep your tyres inflated and replace them every few years. Any cargo weight you carry in the trailer should be over the wheels or in front of them. And just allow for extra braking distance to cope with other drivers doing silly things.
Trail or tent and folding camper camping is insanely cheap fun. Welcome to the fold!