Spring is here, which means some people are gearing up to make what could be the largest purchase of their lifetime: a home. In many parts of the country, would-be buyers are finding that there aren’t enough homes on the market. That could lead them to move more quickly than they would like to increase their chances of getting the home they like, says Tim Manni, a mortgage expert for NerdWallet, a personal-finance site. The home-buying process can have many moving parts, and even people who aren’t rushing the process can make mistakes.