Photo: Heather Charles / Chicago Tribune 

Q: We own a two-flat in Lincoln Square and our tenant has expressed interest in buying it. We would do this without a real estate agent, and we want to pull some comparables in the neighborhood so we can determine a good asking price.

I notice in your column that you often quote sale prices on properties, and I assume this is public information. How does a civilian like me who is not a real estate agent access this info? Is it online somewhere? —Amy

A: The information is public, yes, but you need to know where to look. But first, Amy, keep in mind that in a neighborhood like Lincoln Square, where sales have been rather healthy this year, you should pay attention to the latest data possible. Price increases have been fast and steep enough that even something sold in December or January may be below the present market value of your home.

Here are a few routes to finding prices on comparables:

If you know of some recent sales of comparable properties, start with Type in the address of a property, and up will come its sale price and price history—such as where the price started when the property first came on the market, and when the sellers cut the price. (You’ll need to register at the site to get access to this information; registration is free.) The page for that property will also offer a chance to see similar properties. Click there and see what two-flats near you have been selling for recently. You can also try typing in your own address, which will bring up a “not for sale” page. It may offer similar properties, as the sold pages would.

Again using the address of a recent sale, go to Type in the address and you'll get a Parcel Index Number, or PIN. Take that PIN to Click “search our records,” and put in the PIN when requested. That should pull up all public transactions, such as mortgages, liens and quitclaims, going back to about 1988. Look for a warranty deed, which is the document for an open-market sale. You might also see a trustee deed. Either way, click the latest one and see the amount that is displayed on the next screen. (Trustee deeds often do not show an amount.)

These two will give you broad-brush coverage on prices that doesn’t take into account the differences from one property to another than might influence the final price. For example: one property has a two-car garage and the other has a one-car. As a “civilian,” you don’t know how much to adjust the price to reflect that difference.

That’s why the safest way to go is to have an appraiser come in and do a full-scale appraisal of the property. The appraiser will have professional access to good information on the latest and most comparable sales, and is trained to add pluses and subtract minuses from those comps to get to the best possible estimate of the current market value of the property. This will cost more than the two methods I already suggested (which are free), but will be enormously more precise. Because of its precision, it will help ensure that the price that you and the buyer agree on is one that a lender will underwrite—assuming that the sale-time appraisal comes out with a number pretty close to the one the first appraisal did.