Start with duration, honestly
Almost every rent-or-buy calculation begins by dividing the purchase price by the monthly rate to find a break-even point. That is a reasonable first cut, and it is wrong often enough to be worth checking.
It is wrong because it assumes the requirement is fixed and continuous. Most are neither. A site that needs a generator for eleven months, then not at all for two years, then again for six months, has a very different economic profile to one running continuously for eighteen months, even if the total hours are similar.
Be honest about which you are. If you cannot state with confidence what the requirement looks like in three years, that uncertainty has a value, and hire is what buys it.
Capital versus operating cost
The two options do not just cost different amounts, they cost differently, and on most balance sheets that matters as much as the total.
Purchase is capital: a large single outlay, an asset on the books, depreciation, and often a competing claim against other capital projects. Hire is operating: a predictable cost that can usually be charged against the job, the site or the event that caused it, with no asset to carry.
For project-driven businesses that second point is decisive. A hire cost attaches cleanly to the job that incurred it. A purchased generator has to be allocated across every job for years afterwards.
What ownership actually costs
The purchase price is the beginning of the number, not the number. A fair comparison includes everything that follows it.
- Installation. Pad, cabling, changeover switch, fuel system, exhaust, acoustics, commissioning.
- Scheduled servicing every year, including the years it never runs.
- Load-bank testing to prove capacity, on the interval your risk justifies.
- Fuel management. Stored diesel degrades; it needs turning over, testing and sometimes polishing.
- Consumables. Batteries, coolant, filters, belts and hoses on their own clocks.
- Compliance and records. The documentation that makes the asset auditable.
- Depreciation and space. The asset ages and occupies a footprint whether or not it earns.
None of this argues against buying. It argues for comparing like with like, because a hire rate already contains every one of those items.
What you give up either way
Buying costs you flexibility. You own one machine at one rating. If the site grows, the load changes, or the next job needs something different, you are working around the asset you have. Specification decisions made once are lived with for a decade.
Hiring costs you availability and, eventually, money. On a genuinely permanent, continuous requirement the rate stops making sense, and a hire set is not sitting in your plant room waiting for a fault at 3am the way an installed standby unit is.
Those are the real trade-offs. Everything else is detail.
The exit nobody plans for
The end of the arrangement is worth thinking about at the start, because it is asymmetric.
Ending a hire is a phone call. We disconnect, load out and take the equipment away.
Ending ownership is a project. The set has to be decommissioned, disconnected, removed, and then sold, traded or scrapped, and the price you get depends heavily on whether it has a maintenance history. A well-documented machine retains real value. An undocumented one is sold on hope.
If you are buying, budget for the servicing that protects the residual. If you are weighing the technical side of the same decision, we cover it in hire or buy. Either way we do both, and we service what is on your site whoever supplied it.
