[I just ordered a 1533 with FEL and BX80 bachoe.... I know that the tractor is around 3000lbs .... but i assumed with the FEL (500lbs) & Backhoe (700lbs) that i would be around 4200lbs.... is this a bad assumtion....]
I'm looking at the weights also, but for the MF1540 not MF1445. I haven't ordered a tractor yet, but have it narrowed down to a MF1540 or JD3520. I think the 2 tractors and implements should be very similar in weight. Anything bigger and I wouldn't be able to tow it with my 95 Chevy truck and 7000GVW trailer.
I found weights for the JD3520 and some attachments
Tractor 3000lbs with fuel and etc.
FEL 671lbs : HD bucket with edge 297lbs :: 968lbs
47 backhoe 974lbs : 20" bucket 109lbs :: 1083lbs
448 bachhoe 1474lbs: 24" bucket 116lbs :: 1590lbs
Total is 5051 with little hoe and 5558 with big hoe.
Most 7000GVW trailers have a legal towing capacity of 5500 pounds. So, the smaller hoe would be towable, and the larger hoe would not be. But one could take the buckets off and put them in the box of the pickup to get the bigger hoe down below 5500 pounds. I don't think the tires could be loaded.
Depending where you are, a trailer of 10,000 GVW or higher may require a CDL license.