Experts

"As this case was tried without a jury, this Court's authority is as
broad as that of the trial court, and this Court may render a judgment
it finds warranted by the facts, taking into account in a close case
the fact that the trial judge had the advantage of seeing the
witnesses" (State Farm Mut. Auto Ins. Co. v Stack, 55 AD3d 594, 595, citing Northern Westchester Professional Park Assoc. v Town of Bedford, 60
NY2d 492, 499). As the Supreme Court's findings and determinations
concerning liability were warranted by the facts, they will not be
disturbed (see Stojowski v D'Sa, 28 AD3d 645; Manzo v Gross, 19 AD3d 379; Chambers v McIntryre, 5 AD3d 344).

…

The Supreme Court also properly
dismissed the counterclaims based upon its conclusion that the
testimony of both experts was of no probative value. "The opinion
testimony of an expert must be based on facts in the record or
personally known to the witness. . . An expert may not reach a
conclusion by assuming material facts not supported by the evidence,
and may not guess or speculate in drawing a conclusion" (Quinn v Artcraft Constr., 203 AD2d 444, 445, citing Cassano v Hagstrom, 5 NY2d 643, 646; see Shi Pei Fang v Heng Sang Realty Corp., 38 AD3d 520, 521; Cappolla v City of New York, 302
AD2d 547, 549). Here, the record is clear that the contractor who took
over after the plaintiff's involvement was terminated lacked the
"requisite skill, training, education, knowledge, or experience to
render a reliable opinion" on the quality of the home repair done at
the premises (De Hernandez v Lutheran Med. Ctr., 46 AD3d 517, 518; see Matott v Ward, 48 NY2d 455, 459; Miele v American Tobacco Co., 2 AD3d 799, 802; Pignataro v Galarzia, 303 AD2d 667, 668; Karasik v Bird, 98
AD2d 359, 362). Additionally, since it could not be determined whether
certain damages were caused by the plaintiff or existed before the
plaintiff started working, or whether seemingly defective work was, in
fact, work that the plaintiff could not complete because its
involvement in the project was terminated by the defendants, any
conclusions as to damages caused by defective workmanship could only be
based on assumption and speculation, not on facts in the record or on
facts personally known by the witness (see Shi Pei Fang v Heng Sang Realty Corp., 38 AD3d at 521; Cappolla v City of New York, 302 AD2d at 549; Quinn v Artcraft Constr., 203 AD2d at 445).

Similarly, because the construction valuation expert did not see
the premises before the plaintiff commenced work on it, he could only
speculate as to what had been demolished and how much labor had been
involved. Thus, his conclusions, too, were not based on facts in the
record or personally known to him (see Shi Pei Fang v Heng Sang Realty Corp., 38 AD3d at 521; Cappolla v City of New York, 302 AD2d at 549; Quinn v Artcraft Constr., 203
AD2d at 445), and the court providently exercised its discretion in
disregarding his testimony and report regarding the plaintiff's alleged
overcharges. Without the evidence provided by the experts, the
defendants failed to meet their burden of proof on their counterclaims (see Feldin v Doty, 45 AD3d 1225, 1226; Weinberg v Finkelstein, 112 AD2d 218, 219; De Vries v De Vries, 66 AD2d 832).