Bill, for sub-20-unit multifamily in Tarrant County, I'd start by asking investor-focused agents directly how many small multifamily deals they've actually closed in the last year — not just listed. A lot of agents say they "do multifamily" but spend most of their time on single-family. Ask who brings them off-market deals (property managers, wholesalers, other investors) and how quickly those go. I'd also interview at least two or three and ask each one to walk you through a recent off-market deal — what the numbers looked like and how they found it. A knowledgeable local Realtor who lives in that space will have a pipeline you can feel in the first conversation. Good luck with the search — Tarrant's a competitive market for small multifamily right now.
Bill, a few things that have worked for people chasing small multis in Tarrant County. Tarrant Appraisal District records show who owns each property, so when you spot a 5-19 unit building you like, you can look up the owner and reach out by mail; a lot of the older ones in Fort Worth, Arlington and Haltom City are long-held by individuals. Brokers who mostly sell 20+ units often pass on the small stuff, so ask agents who do 2-4 and 5-15 unit sales, and ask them for pocket listings by name. One thing to plan around: 2-4 units can use residential or DSCR financing, but 5+ units moves to commercial underwriting, which looks harder at the T-12, rent roll and property condition, and usually takes longer to close. Having that lined up ahead of time is what lets you move fast when an off-market seller says yes. Disclosure: I'm a lender in Texas.