I built one this last summer all though i all ready had the metal laying around the ranch but i spent a little extra and bought a heavier jack than what i really needed. But still only spent about 60 dollars on that. I used the plans that i found on the internet and they were fine, i did though instead of using 1x3 in rectangular tubing for the uprights i used 1x1 tubing, just make sure its at least 8 guage tubing, and its plenty strong enough, ive had all my sled up on it and havent had a problem. Another thing you want to watch for when your buying your jack is that you have to have enough travel, depending on how high you want your sled off the ground. For mine to be fully extended and to set low enough on the ground to get under your sleds you have to have more than 10 inches of travelin your jack. I looked up the jack i bought from Northern tool it has 15 inches of travel, 5000lb capacity and cost 44.99 +shipping.