well you have the semi, but no trailer notations for it.
--you do not have a modified pickup truck with flat bed, or anything like that with a goose neck trailer or a BP (bumper pull trailer).
--you have licence to drive the semi....
larger equipment hauler? with correct trailer? some jobs just demand heavier / bigger equipment to get the stuff done. vs smaller size tractors / equipment.
say
uShip - The Online Shipping Marketplace - Ship Freight, Furniture, Cars or Moves and see about bids for equipment hauler to haul stuff for other folks, not much driving of the equipment beyond loading / unloading. but shrugs. it might help pay for a heavier duty, longer, low boy or like trailer for your 2005 Freightliner semi, that is more geared for heavier taller equipment. so ya not taking out a bridge with an excavator or a TLB (tractor loader backhoe) or the like, do to height issues.
have seen many combines, bigger agricultural tractors, dozes, etc... go down the road, some times requiring notation of extra wide or over wide banners being placed on semi / trailer.
a big enough truck and trailer are by no means cheap to buy. to haul stuff from job site to job site. are you wanting to down grade? and be more of a landscape person? with smaller stuff? or be more of a bigger crew of folks with bigger machinery? or be a one man person that does the rough stuff say with a dozer, or a TLB or some such?
TLB (tractor loader backhoes) = pond digging, basement digging, digging out stumps,
grappel, moving garbage piles of crud to a better area, to be burned / placed.
dozers, pushing stuff over, leveling things out.
agriculture style TLB were backhoe comes off, being able to use other 3pt hitch implements. ((industrial TLB's the backhoe most likely does not come off for access to a 3pt hitch))
tract machines, brings up a bigger issue of service tracts, they are a different monster vs wheeled vehicles. from just general maintenance, to simply repairing them / pulling tracts back on if ya break one. to other.
does your driver licenses, let you handle/drive dump trucks for your area? do you have access to some spot for fill material or to get rid of material (dirt, trees, etc...) and do you know the requirements / regulations of doing so?
septic tank and septic field digging... are you familiar with installing of these? along with not driving over them without destroying them.
are you familiar of how close you can get to a home with a basement? without destroying basement wall if you have to drive up near one?
are you familiar with paper work to put in a driveway as in actually going across the ditch, and connecting it to the road out in front of the property?
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how much experience do you have at leveling things out and more so sloping? dealing with erosion control? are you familiar with any of the federal, state, county, specific paper work that needs to be filled out and submitted, there is a lot of erosion control stuff out there, in how to deal with it, and submitting plans to government. are you familiar with OSHA requirements? are you familiar with different types of "compaction" and how to achieve it?
some of the stuff requires sign off via an engineer before work can start.
how familiar are you with of different machines out there? more so industrial machines? not just a general tractor.
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if your lacking in something, then read up on it, on the internet to familiarize yourself with it. it is not a monkey see, monkey do thing at times, but skill, both operator skill, and other knowledge.