My goal with this house, our last house, was to go into retirement in 10-12 years with a low maintenance house that doesn’t cost an arm and a leg to run when my income becomes more fixed.
Deals on PV equipment keep appearing, and we're amazed at how cheap it has become. Maybe prices will come down further, maybe not. Partly, technology development and mass production drove cost reduction, partly economic disruption that left excess capacity. But even when the latter happened (2008/2009) and PV at utility scale got down to $2/watt, volume manufacturing and competition has since driven the cost down to $0.50/watt.
For that, you can buy PV panels and grid-tie inverters. Including balance of system, easy to stay under $1/watt (e.g. 7500W grid-tie system for $3750). At that cost, you can make your own power for $0.05/kWh (cost amortized over 10 years), or break even with $0.20/kWh utility bills in 2.5 years and free after that.
PV panels should last 25 to 40 years. Inverters should last 10 to 20 years.
Of course, utility rules get changed to take away the benefits (make you return as a profitable customer) by either not letting you bank/use power for free, or otherwise giving small credit for power produced, charging large price for power drawn from grid. Batteries are one way to avoid being subject to utility rate games. People are buying battery systems even when they cost more per kWh than just buying power from the utility. Eventually they should be cheaper, but today only when bought through grey-market channels as individual cells and assembled DIY.
Batteries may last 18 months (deeply cycled sealed lead-acid) to 10 years expected from lithium, in some cases 20.
I suggest avoiding use of batteries for now unless you need them. Maybe a small battery-backup system if keeping phone/internet going during outages is desirable. I have a relatively small battery bank as part of a system that lets my grid-tie PV supply the house including A/C during the day. It isn't particularly cost-effective, more of a luxury/toy just because I could. If there is a suitable "hybrid" inverter which works batteries-optional and is grid-tie, that might be best. Of course, in 10 years who knows what battery chemistry will be competitive; the inverter may not have a charge profile which is compatible.
Installing PV panels on the roof today with any quality grid-tie inverter could be the way to go (assuming suitable net-metering rates). In the future, you might replace the inverter with a battery-based system go get around unfavorable rate changes. But you will probably have already enjoyed years of free power.