A "3" row planter? That is odd, I have seen 1 row, 2 row and from there on have always been even number of rows.
As to the weight of the planters you do not mention anything about fertilizer and that would be your big add on weight. I have a 4 row set on wheels and just based upon that think a true 3 row with NO fertilizer would come in about a 1,000 pounds. Add 150 to 250 for seed depending on the type of seed and size of seed hoppers you have.
If you do not mind some basic advice (I bought mine two years ago and just used this year for first time:
Be sure of the row spacing that it suits what you want. Some are not adjustable.
Test the drive wheel for each planter and be sure it turns, wiggle it and all blades for worn bearings. Some of JD bearings have races that are hard to remove. At least mine are with the design, no shoulder to use to tap them out.
Check to be sure it has set up for what you want to plant, if not be sure you know how much the necessary change over from say beans to corn is.
they also make them in no till and full till design, be sure which you are buying if you want No till.
Mine are at least 25 years old and I really like them.
Will suggest you look up Shoup.com for pricing on parts. think have their name spelled correct.
