What's Actually in a Solar Quote: A Maryland and DC Field Guide

A residential solar quote in Maryland or DC has 12 to 15 distinct line items, three different warranty terms, two production estimates, and a savings figure that depends on assumptions you will never see unless you ask. Most homeowners look at the bottom number. The bottom number is downstream of everything else.

This guide walks the line items in the order they appear in a typical Aduu quote, calls out where to push back, and notes the Maryland and DC details that change the math.

The seven things every quote should show

• System design with panel layout. A roof rendering showing where every panel sits, panel count, per-panel wattage, and total system size in kilowatts. If panels land on a roof face you would not pick yourself, ask why; sometimes it is correct (a south-facing edge needs setback for fire code) and sometimes it is the installer optimizing for crew speed.
• Equipment list with brand and model. Panel brand and model number, inverter brand and model, racking system, and any optimizers or microinverters. Generic descriptions like "Tier 1" are a flag. Aduu's residential solar installs typically use Enphase IQ8 microinverters and IronRidge XR rails, and our quotes name both on the front page.
• Annual and monthly production estimate. Annual kWh is the headline. Monthly kWh tells you whether the model accounted for your shade and orientation. December production should land around 40 percent of July for a south-facing system in Silver Spring or Bethesda. If December and July look similar, the model is wrong.
• Itemized price breakdown. Equipment, labor, permits and inspections, interconnection fees, and any monitoring or service contract should each have their own line. A single 'system price' makes it impossible to compare bids.
• Incentives applied to the math. Whether the federal residential ITC is included (it is gone for systems placed in service after December 31, 2025), whether the MEA Maryland Solar Access $1,000 grant is included, whether SRECs are forecast as cash or as a credit against system cost, and at what price.
• Full warranty stack. Panel power, panel product, inverter, installer workmanship, and roof penetration are five separate warranties with five different lengths. Quotes often list one number and leave it ambiguous which warranty it refers to.
• Financing terms. If it is a loan, the APR, term, and total finance cost. If it is a lease or PPA, the monthly payment, the escalator (annual percent increase), and the buyout terms.

The line items that actually move your price

Most quotes show a single dollar figure. The breakdown beneath that figure is where two bids on the same system can differ by 20 percent. The biggest swing usually is not panel brand. It is the installer's overhead and how aggressive their sales channel is.

What a permit actually costs in Maryland and DC

Permit fees are small relative to the project but worth knowing because they are easy for a quote to round up. In Montgomery County, the residential rooftop solar permit fee is $227.12 under the FY2025 Department of Permitting Services schedule, and you also need a separate electrical permit. In DC, residential systems under 15 kW pay $250 to the Department of Buildings, plus a 10 percent enhanced fee surcharge, for a total of about $275. DC also offers a Solar Instant Permit for one- and two-family properties, which clears in days rather than weeks.

Equipment specifics worth pushing on

Once a quote names the panel and inverter brands, you can verify two numbers from public datasheets before you sign: the panel power output guarantee at year 25, and the inverter warranty length.

Most Tier 1 panels (Q CELLS, REC, Silfab, JA Solar, Panasonic, Maxeon) carry a 25-year power warranty that guarantees 87 to 92 percent output at year 25. Cheaper panels often carry a lower year-25 floor (80 to 82 percent). The difference compounds over a 25-year hold, and the better panels usually cost only a few cents per watt more.

Inverter warranties vary more than panel warranties:

• Enphase IQ8 microinverters carry a 25-year warranty, panel-level monitoring, and simpler shade handling.
• SolarEdge string inverters with optimizers carry a 12-year standard warranty, extendable to 25 years, with per-panel monitoring.
• Generic string inverters often carry a 10-year warranty and have a single point of failure.

For Maryland and DC roofs that get partial shade from chimneys, hip valleys, or mature trees, microinverters or optimizers are usually worth the up-charge.

Warranties: read all five, not just "25 years"

Solar warranty terms get conflated in marketing because "25-year warranty" reads better on a flyer than five separate numbers. The five warranties:

• Panel power warranty (25 years) comes from the panel manufacturer.
• Panel product warranty (typically 25 years) also from the manufacturer; covers physical defects.
• Inverter warranty (10-25 years) from the inverter manufacturer.
• Workmanship warranty (10-25 years) from your installer; covers wiring, mounting, labor.
• Roof penetration warranty (10-25 years) from your installer; covers leaks caused by mounting.

Workmanship and roof penetration are the warranties that depend on your installer staying in business. Ask how long the installer has been operating, who pays for service calls, and whether the warranty is transferable if you sell the home. A 25-year workmanship warranty from a four-year-old company means something different than the same warranty from a contractor who has been on roofs in Montgomery County for a decade. See what our warranties actually cover for the specific terms Aduu attaches to every install.

The Maryland and DC specifics that change the math

Net metering treatment

Maryland's net metering rules give residential customers full retail rate credit on excess generation, with credits rolling forward indefinitely. PEPCO and BGE both follow this. DC has its own net metering structure with annual reconciliation; the treatment of unused credits is summarized differently across published sources, so verify the current rule against your most recent PEPCO statement and the DC PSC tariff filing before signing.

MEA Maryland Solar Access Program ($1,000)

For income-eligible Maryland homeowners, the MEA program pays $1,000 per residential project (1 kW minimum). The FY26 application portal closed April 17, 2026 after total funding requests exceeded the $12 million budget. FY27 funding is expected to launch in summer 2026. If your quote includes this $1,000, the installer should specify whether it is a guaranteed deduction or contingent on your application being approved in the next funding cycle. Our Maryland and DC tax incentives page tracks the current state of every program Aduu applies to a quote.

SRECs

Maryland SRECs trade around $40 per credit in 2026, with a $45 SACP ceiling. Systems energized after July 1, 2024 receive 1.5 SRECs per megawatt-hour under the Brighter Tomorrow Act multiplier. DC SRECs trade much higher, typically $352 to $455 per credit, with a $440 SACP ceiling. If your quote treats SRECs as cash applied to the system cost, ask at what price and over what time horizon.

Lease, loan, or cash: the comparison that changes lifetime savings

Three financing paths cover almost every residential install: pay cash, finance with a solar loan, or sign a lease or PPA. Cash and loan both put you on title to the system; lease and PPA leave the system owned by a third party. That ownership difference drives most of the lifetime-savings gap.

Our financing options page breaks down loan, lease, and cash side by side with current APRs and term lengths.

What to do with the quote in front of you

If you have one quote, get two more with the same system size and equipment specs, line up the breakdowns side by side, and look for the line items that vary most. Sales and marketing overhead is where bids diverge the hardest. If you have a question about any line in your quote, including ours, send the PDF and we will mark it up for you.