My husband and I are contemplating home ownership for the first time. We have lived in our community as renters for a couple of years, feel really invested/attached to it, feel that the home prices are affordable, that the neighborhood is up and coming, and can easily see sticking around for quite some time. Although we have always discussed home ownership as a possibility somewhere down the line, mostly we have been relieved to be renters and to avoid the headaches that come with home ownership. BUT, we recently found out that our favorite house on the block is going to be put on the market this spring. We asked the current owners about it, and they invited us over to take a look in a few days. Nerve-wracking, to say the least, since we have not been house hunting at all yet but may have an opportunity knocking.
In the meantime, we have a lot to start thinking seriously about.

Some questions that I've already jotted down to ask are:
Has an estimator come in yet to assess the home?
What work has been put into the house wince it's purchase 13 years ago?
How old is the roof?
How old are appliances such as fridge, dishwasher, washing machine, etc?
Is there central air? If so, when was the system installed?
How old is the hot water heater?
How old is the septic system?
have there been any other property issues that we should know about?

Can anyone suggest additional questions/resources that we should be starting the conversation with? Does anyone have knowledge about properties that use well water (as the properties where we live do), and what to ask with regard to upkeep? Anything else we should be considering?

You should hire your own local inspector. He or she will go over the house with a fine toothed comb, and will point out anything he or she can't or won't inspect directly and recommend additional inspectors (e.g. a septic inspector). You may not be at that stage now but make sure you do so before you finalize any home purchase.

For now, I know at least one inspector in my area has a list of things he checks on his website. You could look for some websites of inspectors in your area to see a similar list.

If you're willing to do this as a newbie, you might consider asking them to forgo a real estate agent (you'd do the same) and use your own or a third-party real estate attorney instead. In WA the seller pays all agent fees, so they'd be able to reduce their price and take a bit more profit for themselves.

This is only if you really want to buy, of course, and if you feel like you're all starting from a good spot together.