A lot depends on when an old house was abandoned. If it was in the 1800s than there is usually few coins but also little iron. The coins are always good ones! If the home was abandoned the 1900s, there will be more coins but also lots more junk iron! Also the more children to play and lose coins seems to make a difference! Farm field and woods cellar holes are tough to hunt thoroughly so after a few fruitless trips, you might find some good coins, wondering how you missed them. This happens to me frequently.. So I hate to give up on a site!
Course if it was abandoned in the 1800s but someone had buried a crock of coins like I believe my honey hole farm field is.. then "OH BABY!" The coin count was way to high to be ordinary yard finds. At that site, I have found one Seated Dime, a half dime, a few 2 cent pieces, a couple of 3 cent pieces, a couple of Spanish Reales, several King George Coppers, two flying eagle pennies, a 1799 half dollar, many many Large Cents as well as many colonial buttons and musket balls! Now I never found anything close to that at one site in 25+ years of detecting!