We're not "do-ourselvers" for electrical stuff, but our solar installer did a nice job of transferring three 100 watt panels from our previous coach. We have a 2010 2551. These are pretty compact sized panels from AM Solar in Oregon (who specialize in RV solar). Two panels run vertically (front to back) along the driver side, one on the passenger side. They pretty much avoid any shadowing from roof stuff like aconditioner, roof vent covers, etc (our covers have a low profile). We can tilt the panels if we really want to stay somewhere a while, and position the coach so they can tilt toward the south in low sun spring/fall/winter scenarios.
He brought the cabling down along side the bathroom vent that is in the narrow closet next to the shower. Then went under the coach and tied everything into the batteries and existing inverter. The 30 watt MPPT solar charge controller is installed just under the sink, in the same neighborhood as the water heater switch etc. -- an easy reach from the battery area.
Two AGM 6v batteries (Lifeline) fit snug as a bug in the battery tray. Have to remove the battery compartment cover to pull the tray out, becuz of height with the cabling attached, but with AGM we won't have to do water maintenance, so that's not an issue.
Would have put in (4) 6v for more battery storage, but installer would have had to build a new longer tray from scratch, so we're going to live with this, and think it will be fine for our present usage (no longer full timing). There appears to be JUST enough room for a longer battery tray, but would be custom built.
Yes, solar is a luxury and expense, but we were able to get federal and state solar tax credit (as second home!) and have had this system on two other coaches. Spend a lot of time in the SW, and can't imagine not having solar (our home does too!).
While we were at it, installer moved the remaining 110 AC outlets circuit to the inverter. Which is great for using all outlets while dry camping, or inverting going down the road. It's an iffy decision because the Norcold refrig is on that circuit too, so if the refrig is on AUTO, it would automatically draw power from the inverter. We're training ourselves to just use the LP and ELEC setting -- depending on if we're dry camping or plugged into power. I think having the refrig run on the inverter while traveling might be a bonus convenience for long trips, and not having to worry about LP for keeping food cool, going into gas stations, etc. Haven't tested that option yet. Anyway fingers are crossed on the decision about the refrig, and hoping we don't have a costly "senior" moment.
Deena