Hello Stef,
I am new to the forum and so just got your meassage. What you are considering is a huge undertaking. I have lived a large part of my life abroad, and there are many things to consider before deciding to come here.
I have lived full time in Paraguay for three years, but bought my house and some other property back in 2008, so maybe I can give you a bit of advice.
Alot depends on the type of life you want to live here. When I came to stay for three months in 2006, I was a single guy, living a bachelors life in the richest part of Asuncion (Carmelitas). I rented a a luxury condo, with three floors, two balconies, and a lived the party life. My rent was $500, and I blew as much in clubbing, dating, restaurants. This will surely cost much more today.
I am now married and have a small son, so I now live a much more conservative life and my costs reflect that. If you are looking for inexpensive living, I would recommend living outside of Asuncion, but this will pose some challenges on its own.
Another important point: Do you speak spanish? This is essential if you expect to get by here.
Best of luck,
Mike