You could spend as much as 50,000 USA and still get disappointing results.
Most houses do not have enough South facing roof area for 3500 watts, assuming you are in the North temperate zone. Repairing a leaky roof will be much more costly with the solar panels. If you put your panels close to the ground, neighbor children will play on them. Besides damage, you could be sued if a child is injured. Thieves may steal your expensive panels.
Many locals have an average of several hours per day, cloudy = output drops to about ten watts. Your 3500 watts could drop to less than 1000 watts except for an hour or two on average December days. Worse, if you are at the latitude of Nome, Alaska.
If I had the money to build a house that favored our planet, it would be one story, with a flat section of the roof that serves as a patio. The solar panels would be a sunshade and shelter from the rain, about a 45 degree slope = optimized for October and February, instead of August and April which is about 20 degrees where I live in Northern Florida. That would give me about 1/4 as much power to charge my batteries in December as in June instead of the 1/10 th for a flat roof. Eventually, my utility won't want to buy electricity in June at 1 pm as they will have too much. Some of the roof would face South West as I think the local utility will favor SW facing roof as they will have too much solar electricity early afternoon and not enough late afternoon when the peak demand begins. That is likely several years in the future when solar panels are less costly, so near term I would only install about 1000 watts for my patio roof, which I might enlarge later. I think a fixture can be designed to operate 4 florescent tubes, efficiently at 390 volts dc. To get 390 volts at 13 volts each, I need thirty 110 amp-hour batteries. I'm guessing I need about that much to charge the electric car of the future. The Tesla motor car has a 375 volt battery, so I could do a quick charge in perhaps 15 minutes removing perhaps 30% of the amp-hours in my 30 batteries = significantly more efficient than using an inverter to change dc to ac, then, ac back to dc to charge my electric car. If my car needs more amp-hours, I can get a few from my utility connection at the same time, I'm making a big dump from my 390 volt battery.
Since my panels only total 1000 watts on brightest sun days, typically the utility supplies most of the power = I want to recharge my batteries as quicky as practical. When the utility voltage drops a few volts = brown out, my share increases up to the rating of my inverter, briefly, and large loads in my house such as cloths dryer, water heater, cook stove, pool pump, TVs that no one is watching are shut off automatically. If the brown out turns into a blackout the computer decides priorities with human veto. If the blackout lasts more than a few hours, tight rationing will be essential, to avoid damaging $2000 worth of batteries, especially if the 390 volt battery started the black out at half charge. 30,000 watt hours = 30 kilowatt-hours gets used quickly in a modern household. Neil