Shower access only needed (Around NW 50th may-portland area)

This might be a very strange request but we are a couple and we are looking for access to a shower only.
We do not need a room we have access to sleeping quarters inside our business.
All we're seeking is just access to shower facilities that are clean (we will maintain) that has good hot water and as close to Mayfair area 50th and May as possible.
Need to be able to have early morning access and or evening access depending on the day.
We are hoping to pay a monthly fee to help cover additional electricity and water Plus.
We are clean, business owners, and again only need access to a shower daily.
We have downsized our life so we don't need a full house or a place to sleep or eat.
We are fine with background checks as well as a security deposit if needed.
We can pay in cash if desired.
Just need a clean, safe, private shower / bathroom.
Thank you very much