Financing and rebates, without the Lake Street pitch.

The most common way two estimates become impossible to compare is that one is a price and the other is a payment. “$189 a month” and “$13,500” are not the same kind of number, and putting them side by side tells you nothing.

Cash price first, always

The number you want on every estimate is the installed cash price: equipment, labor, permit, removal, and startup, with nothing financed and no rebates subtracted. That is the figure that compares across companies. Financing, if a contractor offers it, belongs below that price as a separate term, never in place of it.

If an estimate shows you only a monthly payment, ask for the cash figure before you go any further.

How a monthly payment hides the number

Promotional financing, the zero percent for 18 months kind, is usually offered through a third-party lender who charges the contractor a fee, often several percent of the job. Some contractors absorb it. Many fold it into the price, which means the financed buyer and the cash buyer are quoted different numbers for identical work.

There is nothing wrong with financing a five-figure purchase. But you should know the cash price, the financed price, the rate after the promotional period, and the fee, before you decide. A contractor who cannot or will not separate those is telling you something.

A home equity line or a credit union loan is often cheaper than dealer financing over the life of the loan. It is worth a phone call.

Federal credits in 2026

The federal Energy Efficient Home Improvement Credit, known as Section 25C, covered a portion of the cost of qualifying furnaces, air conditioners, and heat pumps for several years. It expired for equipment placed in service after December 31, 2025. If a 2026 estimate mentions a federal tax credit, ask the contractor to point to the specific program, because the one most people mean is no longer available.

ComEd, Nicor, and what they actually pay

River Forest homes are generally served by ComEd for electricity and Nicor Gas for natural gas. Both run efficiency programs with equipment rebates, and both change their offerings year to year.

Nicor Gas offers a rebate on high-efficiency furnaces: $150 at 95% AFUE or better and $225 at 97% or better on its 2026 application, which is filed after installation. ComEd offers rebates on qualifying heat pump installations. They have been substantially larger than Nicor’s furnace rebate and are normally handled through the contractor or distributor rather than by you. We could not confirm this year’s figure from ComEd directly, so check ComEd for the current amount. Each rebate depends on the specific model installed.

Two questions settle most of the confusion. Is the price on the estimate before or after the rebate? And who files the paperwork, you or the contractor?

Manufacturer promotions

Equipment manufacturers run seasonal promotions, typically in the shoulder seasons, offering a few hundred dollars back on higher-tier systems. They are real, they are short, and they are tied to specific model combinations. If one appears on your estimate, ask for the promotion name and end date. If it appears on one offer and not another, note it on that row so you can see whether it explains a price gap.

What to ask for in writing

Four things, on every estimate: the installed cash price, any financing terms and the rate after the promotional period, any rebate or promotion cited by name, and whether the price shown is before or after that rebate. With those four, two estimates can be compared honestly.

Nothing on this page is tax, financial or eligibility advice. Whether you qualify for a utility program is a question for the program, and what a loan costs you is a question for someone who knows your finances.