First I think you need to put the numbers on table, what is the market like, how much work or rental business can you backlog, operating costs and depreciation of said equipment performing the work, include repairs maintenance, don't ever forget the undercarriage (tracks) is an expensive wear item and has only so many hours of use before it needs replacement. Every hour you operate this tractor, it has to be factored in.
Rental business, I would take into consideration JD's advice, many people know nothing about operating heavy equipment, how to perform excavation, grading, clearing tasks, or what have you. They also, like renting a car, could give a rats @ss about your equipment - worst case scenario. That is a combination that will get costly if you have to absorb the repairs or retrieving a machine.
Ideally you want to know who would operate it, what their experience is and what the site looks like, now you mention with an operator(you- your husband or an experienced operator?) that would be the smartest approach, an experienced operator who can handle the machine, knows how to work a site, dewater, grade and knows when to stop, meaning, too wet, too much rock, too small of a machine etc. etc. etc. There is no substitute for an experienced operator, trust me on that, I've been there, as I did it for a living for many years, absolutely a must to make sure the operator knows what they are doing, greases the machine, looks it over carefully everyday, tops off fluids and makes sure the tracks are adjusted when needed, as well as regular maintenance
The other option is you are an excavation contractor, which is different from a rental business. In that situation you look at a site, estimate what the work will be, cost load your equipment, operator, fuel, insurance, all direct and indirect costs, sign a contract with an owner and agree to perform the work per contract agreement, to go this route you need an experienced person to estimate the job and cost load it so the number is profitable, but don't ever forget unforseen conditions and make sure there is a clause in the contract stating so, covering you in case rock or water is encountered, you don't want to be liable for any extra work over the base bid price.
You could provide the machine, operator, after looking at a site and once you have established a profitable rate, that would be much safer than renting to a person of unknown skill, experience on a site that you have never seen.
Insurance, most rental places in this area require the customer to provide a $1,000,000.00 policy, same as a contractor renting equipment, though one did not and provided coverage through the national rental association. I used to rent from them, new D4G CAT $450/day at that time they provided adequate insurance and I was careful in my work, all on the surface anyway. You had more liability but your costs were less, it helped keep my jobs profitable. Insurance as a contractor, is expensive, last I checked, was $10,000/year for excavation and probably minimal coverage, very costly, you need to have the backlog of work to justify it. When I rented any of their equipment, I took care of it, grease as needed, cleaned the cab, kind of the exception as so many others don't, the service was well appreciated, in turn they always gave me a good deal and my jobs always made decent money. They are out of business now, but not because of the rental side, think it was their dealership that may have did it, not an easy business to sustain.
