I wouldn't advise seeing gents in a space that has no shower. First of all it means that they can't take a shower when they get there or when they leave. Secondly, it becomes rather obvious that you can't take one in between appointments...

Also, you are talking about a situation where strange men are coming and going all day in an office building environment.  If you think this will go unnoticed by other commercial tenants you need to think again.

^^agreed, hotels are the best choice.  Eventually your commercial neighbors will notice something odd.  Besides that I don't think there's a way to get around not having a shower.

I understand the draw of a fixed location, fixed costs...  but it lacks the security of being able to change locations.  I just can not recommend it.
I know of one FBSM practitioner, who uses medical attire...  opens the front but does not undress.  She has a commercial space.  While there is access from a hall that has a store front door, the hall also has a rear access right beside her location.  She has a space intended for a kitchenette but no shower.  
If one had money to spend, a shower could be built with a pump to put water into a sink...  but this is an added cost & complexity.  

I do know one provider who works from home...  she has a legit home office business which is a cover for her limited extra activities.  Her legit business just does not bring in enough.  

That said, I don't think it is wise to work from a fixed location.
skb

TL,
Your pictures are stunning, your donation is reasonable.  I can not imagine that you'd not be successful.  
My suggestion is to be very careful, to use hotels, manage your money very carefully.  You mention credit & debt without specifics (which is fine).  You probably need to work your way into a better finicial situation.  You need to know what debt to pay off first, you need to pay down debt...  be sure not to aquire more.  This takes huge dicipline.  

Take Care,
skb

If you rent in an office building, maintenance will come through during different times of the year to change lightbulbs (fluorescents) and to just check out the place to make sure its in good order.  Also, usually once annually, the Fire Department inspects the premises for fire safety and code violations.  How are you going to explain a bed and no office furniture?  

Plus expect calls from salespeople who show up to cold call your business for office supplies, equipment, etc.  And nosey neighbors who will stop by to see what line of biz you are in, for possible networking.

How about the client who shows up with wine and a Vicky's Secret bag? It can't be your birthday everyday!

Anyone of these concerned parties could become suspicious and blow the whistle!