Well, then, the market seems to be pretty well centered in the area around Loop 820 and North Beach Street, just east of I-35W in the north part of town. There are plenty of extended-stay places around that intersection, and plenty of apartments in that area, too.
My biggest problem with that area, aside from the fact that I'm a west-sider, is that traffic along I-35W and 820 can rival 635's at times, if not in volume then in pace and density. Your gentlemen callers will need to take that into consideration, and it's not a great location for someone whose time is limited.
I think the west side is underserved, but then again maybe it's just me and two other guys out here.
There are a bunch of apartments off of Bryant Irvin Road, just south of the Trinity River, between I-20 and I-30, and convenient to both. I've visited a few ladies at various complexes in that area, and I think an L1 lady may have her incall around there now. Several complexes are located off of South Hulen just across the Hulen Street Bridge; they, too, would be convenient to both I-30 and I-20. Several extended-stay hotels are located in the I-20/Bryant Irvin area.