If you are a Sam's Club member or know someone who is, see if your local Sam's has or will get you a 122442. This is a Goodyear Racing engine hoist. It comes with an engine leveler, has low profile leg design (wheels are up in the legs so it will roll under low cars - if you ever used one with casters under the legs, you will understand), folds up, and is a very nice piece. I bought mine for $169.99 plus tax in Tulsa. From the Sam's web site, it may have gone up $7. Unless you are getting the steel for free, I don't think you can build one this cheap, even if it is not as nice. Go to the Sam's web site and search for 122442.
OOPS. I just noticed that most of you are in Europe. Don't think there are Sam's Clubs there. Oh well, those in the States reading this thread should check out the Sam's unit.