Buying the system
A cash purchase makes the equipment an upfront expense. A loan spreads the payments over time. In both cases, clarify the full installed price and who is responsible for upkeep. For a loan, compare the financed price, fees, interest, and total repayments.
Using a system someone else owns
A lease generally charges for use of equipment. A power purchase agreement generally charges for energy it produces. Availability and terms vary. Ask who owns the equipment, who maintains it, and whether payments change over the contract.
Compare beyond month one
A low first payment is not the whole agreement. Ask about increases, extra charges, early termination, transferring the contract when selling, and the options at the end of the term. Make sure incentives are attributed to the party actually eligible for them.
Keep your decision grounded
No payment structure is automatically best for every household. Your budget, expected time in the home, appetite for upfront costs, and the actual offers available all matter. Compare written proposals and seek independent advice for financial or tax questions.
Further reading: U.S. Department of Energy: Solar Financing Guide. Local rules and individual circumstances vary. This guide is general information, not a quote or financial advice.