So if you're saying you don't do less than 90min for outcall, I would re-think it.
I would too. You have access to what amounts to the cheapest, best integrated and easiest public transport in the land, and whilst I wouldn't be bothering with half hours I'd certainly be doing an hour and maybe even 45 minutes.
It's just a hunch, but do you advertise heavy sub stuff and GFE all together in the same ads? I don't mean just bit of spanking or whatever; if the answer is yes then bear in mind that these are two very separate markets and whilst some people will dip in and out, there's a chance that if it's all chucked in together the serious and experienced Dom punters will think you're just playing at it or sticking it in for marketing purposes, whilst the GFE punters are likely to be put off by talk of heavy BDSM stuff, especially if you have photos showing marks on your body and suchlike.
It's fine to have separate ads/personas and I'd keep the niche stuff for niche sites. It also means you can advertise your higher rate for these bookings separately so it isn't constantly being seen alongside your lower one

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