What to expect…..
Because the process of installation can take so long you probably want to limit the amount of time you spend figuring out what you need and where to put it. Most solar companies are going to ask a lot of questions about your habits, the sun vs. shade on your property, and the main question will be your prior years usage. You’ll want to have your information before they show up to help streamline the process.
I am a paperwork packrat. After an IRS audit I learned to keep every possible bit of paperwork for at least 7 years, and keep it organized so I keep every single electric bill. This was super valuable during the solar process we were able to show very clear patterns of usage. If you haven’t done this get on the phone and order your past year or two years of bills.
If you have time start making lifestyle changes and watch your bills closely to recognize patterns of usage and see if adjustments are making any difference. The first thing you can do is replace every single bulb in your home with energy saving bulbs. Beware they are very different from your regular 75w super bright lights. It may take some getting used to. You may want to try a couple different types and see which are the best for your needs.
If you have a year or so before you are ready, start tracking where the sun and shade hit your property. We did this for two weeks in the summer only and found out that our house cast a shadow much longer than we would have ever anticipated in the winter. Winter is the season we needed the most sun and the fewest shadows. Make a map so you can show them specifically where the shadows are in each season.
They are most likely going to want you purchase enough equipment to never have a bill but like I’ve said previously you don’t want to purchase super expensive equipment to sell energy back to the electric company for a fraction of the cost you pay them for it. You need to dig deep and decide what the best senerio would be for you. Also anticipate any future additions and energy efficient appliance purchases. We installed a new on demand water heater and that has cut out us turning the water heater on for days on end. Water heaters are one of the top three energy consumers in your house.
If you are installing the panels yourself you need to be aware that the slope of the panel will greatly effect the efficiency of the panel. That is, you often see solar panels resting at an angle so that it can maximize the amount of sun rays that hit it. If it was completely vertical it would cast shadows on itself and if it was horizontal it would only really get maximum sun once a day at noon in summer. Basically the sun changes its position in the sky based on the season so its not in the same spot at noon in June as noon in December.
The link below tells a very accurate description of the above reasoning:
https://www.spaceacademy.net.au/spacelab/notes/solpanel.htm

Our panels are angled more in favor of winter to maximize the the sun rays when there are the fewest. You will really want to research this subject to make the best decision for your setup. Make some coffee because it can be dry subject matter to read about. You will have to have this answer for the installation crew if you are choosing to have it done for you.