Finding Comps and setting market prices
I am curious, if CRE brokers or owners create CMA (Comparative Market Analysis) report to calculate and set optimal market value of the property.

If so,

1. how do you define comps?
2. What criteria do you use?
3. Where do you get the data or report from? CoStar?
4. How is this different for sales and leasing?

For context, We're building a tool that uses comps + other relevant data to calculate rental prices. 
[{"id": "fvmqsq0", "text": "Similar properties in the same area. Theater vs Theater, industrial condo vs industrial condo, retail vs retail\n\nCostar last 12 months\n\nLeasing is based nnn", "replies": [{"id": "fvmrr3w", "text": "You would have to study the nuances of each individual market. Some leases are reported in gross terms and to understand the trends of the local marketplace, you would have to study the market trends over the past five years, not just the last 12 months", "replies": [], "depth": 2}], "depth": 1}, {"id": "fvmrm61", "text": "Hire a commercial real estate appraiser", "replies": [], "depth": 1}, {"id": "fvmsayq", "text": "There\u2019s a lot to unpack here... Before going into details, what is the primary reason for your question? \n\nShort answer: Comps can be found from sources like property tax records, costar, etc... CRE brokers would likely use comps in conjunction with other valuation methods like applying a cap rate to NOI (income approach) and/or replacement cost approach. \n\nBeyond any appraiser or broker\u2019s opinion, market prices are ultimately set by a willing seller and a consenting buyer who is able to close.", "replies": [{"id": "fvmt4cw", "text": "Thanks. For context, We're building a tool that uses comps + other relevant data to set rental prices.", "replies": [], "depth": 2}, {"id": "fyefrwx", "text": "Is costar the only database for historical lease information for a particular region? Finding signed commercial lease data/rent is difficult to find in my experience.", "replies": [], "depth": 2}, {"id": "g1ca19c", "text": "How can you find comps from property tax records? The information I am looking for is effective rental rate and lease term.", "replies": [{"id": "g1fj6uf", "text": "No you will not find lease comps in property tax records", "replies": [], "depth": 3}], "depth": 2}], "depth": 1}]