I bought a LG front load set with my tax return 3 yrs ago. I love them... yes they were a bit more then the top load, but I wanted to stack them on my bathroom. If I couldn't stack them, they would have to go back in the damp basement & I was having troubles getting up & down the steps carrying laundry w/ being pregnant. Plus, with the big belly it was getting to hard to reach the bottom of the old one.
When we got the new set, our water bill went down about $15 a month and the electric bill went down almost $30 a month. Which means we saved about $540 a year x 3 years = over $1600 in utility saving so far... so all in all they have paid for themself. So, you know we are a family of 5 (6 is on it's way)... and we usually have at least 7 - 8 loads of laundry a week. I do know that if I was to use cold water I would save even more, but I don't.
With you being a single income family - you should get a pretty good tax return this year with all the new credits & changes to tax laws... now is the best time to get it - if you can use your taxes that is.
Also, all washers & dryers are even more efficant then they were even 3 years ago when I got mine. But at the time I got mine it used the least amount of water then any of the other ones... LG is made in Europe where they have strickter use regulations then anywhere else in the world.
Good luck finding the right set for you... it took me about 3 weeks of looking before I bought my set. I hate spending that much money on anything - lol my washer and dryer cost more then my car.