How are you washing and dryring clothes? How are you heating water? How are you keeping food cold? How are you cooking the food? How are you heating and cooling this place? What type of computer and internet connection are you using?
These are all areas in which conservation is possible.
With the numbers you have given us so far (300W solar, 800W wind), I can make a WAG that you might make 3-5kw/DAY. This is less than 10% of your stated energy requirements. Now, if you have $100,000-$150,000 to spend, I think I can come up with some ideas, name some inverters, solar panels and wind turbines that would meet your stated energy requirements. The other option is conservation.
Now you could build a small scale RE system with the components you have listed and run a few small loads off them. Several people on this board have done exactly that. But tying to the grid is a difficult process, filled with regulations, inspections and paperwork.
Lastly, building an RE system for your parents might not be such a good idea, These systems require a certain amount of monitoring, tweaking, and maintinance. It takes a bit of dedication to keep one running properly, it's not like a car where you hand somebody the keys and off they go.