Hi seraphim,
Kits are almost always a rip off.
Since solar is for battery charging between 60 and 150 watts of panels per 100 amp-hours of battery bank is a good range.
The booster inverter will cost more than a second generator--but having only one genny to look after and store is a big advantage.
If you wish to squeeze every possible watt from the panels then look at MPPT controllers. There is a trade off again--good pwm controllers are about 1/2 the price.
A great controller will have temperature compensation, and adjustable set points for charging.
This may help:
Budget-->Battery bank size-->number of watts-->PWM or MPPT.
