Seasonality is the master variable. Cooling season and heating season each bring a surge of installs and emergency work; the shoulders in between can cut monthly revenue sharply while the cost base — technicians you cannot afford to lose to a competitor, the fleet, the shop — stays fixed. Companies that carry technicians through the shoulders keep their best people and own the next peak; companies that cannot, retrain new crews every year. That retention is a financeable investment with a measurable return.
Equipment inventory front-runs revenue. Distributors offer early-buy and volume pricing on units ordered ahead of season, and supply hiccups have taught every contractor what stockouts cost in July. An inventory facility or seasonal line lets you take the early-buy economics without draining the operating account — and the discount captured often covers a meaningful share of the financing cost.
The commercial side bills like construction. New-construction mechanical contracts and commercial service agreements pay on terms — pay applications, retainage on larger jobs, net-30 to net-60 from GCs and property managers. That half of the book supports receivables financing and, at scale, an asset-based facility; the residential service half, collected at completion, does not need it. Structuring around the actual mix is the difference between paying for capital you need and capital you do not.
Maintenance agreements are underwriting gold. A book of service contracts is recurring, predictable revenue — the thing every lender prices favorably. If you have built one, make sure any lender evaluating you sees it broken out; it routinely improves both approval odds and terms.