Nearly $30 million in construction cost overruns on the University of Connecticut’s Hartford campus topped a list of contracting issues that sparked criticism Tuesday from the state auditors’ office. Construction and renovations combined originally were priced at $87 million, and a guaranteed maximum price eventually was set at nearly $98 million. But after the university adjusted the contract 24 times, involving 283 construction-related changes, the price tag ballooned, according to the legislature’s fiscal watchdog agency, the audit reports. Besides the renovation of the Hartford Times building, the project, developed by the Greenwich-based HB Nitkin Group, also included the purchase of an additional building, renovations to accommodate the School of Social Work, a partnership with an interior renovations to the Hartford Public Library, and the leasing and expansion of a new bookstore and café. The audit, which covered three fiscal years running from July 2015 through June 2018, found two construction project and two design contracts — priced between $4 million and $26.6 million — that were not competitively bid. State policy generally requires bids on contracts valued at more than $500,000.