Fortunately, there is an easy test: if they want any money off you in advance, they're a scam. There are real agencies that would like you to pay for pictures, but if they are not prepared to allow you to use your own photos / choose your own photographer / own the copyright of any photos, you can cross them off your list.
There is work for all shapes and sizes, but see lots of other threads about the 'most agencies think only one stereotype is worth marketing' issue. (I'd have to work out what 185lbs is - are you American?)
Like agency work, neither is perfect, but the two quickest ways to start would be either to find a brothel (aka parlour - look on the various 'punting' sites to find one with good reviews = presumably happy staff - where in exchange for having sex with several men and handing over around half the money, your security is greatly helped by having other people around, clients will typically turn up wanting sex with whoever happens to be on duty, and you can leave the work there) or put a profile up on AW (find a security buddy and be ruthless about who you'll consider seeing).
You may get called Lily by some

, but there's only one person with Lilith in their username at AW and she's a dominatrix in Glasgow...