Professional editing is expensive (as it should be). Beta-readers are another less expensive alternative for those without a publisher or self-publishers.
Beta-readers can be found on the literary sharing site I founded www.betareader.us, in LinkedIn, Facebook, and Goodread groups.
Beta-reading/editing is part of and has grown along with the sharing economy. There are a lot of English majors, avid readers, and freaks with great line-reading eyes who are beta-readers and willing to read your book for little or no money.
Nobody should think that a beta-reader can replace a good editor who will devote the skill and attention described by Jann Alexander but if your are looking for someone to work with you at every stage of your book creation there are beta-readers. Another undeniable function of beta-readers is they are numerous — for little money an author can afford to have multiple eyes read their manuscript giving you a better chance of catching those pesky typos that even professional editors and publishers seem to miss.