O.C.G.A. § 24-7-701: Lay witness opinion testimony.

(a) If the witness is not testifying as an expert, the witness’s testimony in the form of opinions or inferences shall be limited to those opinions or inferences which are:

(1) Rationally based on the perception of the witness;

(2) Helpful to a clear understanding of the witness’s testimony or the determination of a fact in issue; and

(3) Not based on scientific, technical, or other specialized knowledge within the scope of Code Section 24-7-702.

(b) Direct testimony as to market value is in the nature of opinion evidence. A witness need not be an expert or dealer in an article or property to testify as to its value if he or she has had an opportunity to form a reasoned opinion.