hardly anyone on here used an agency for a fiancée or spouse visa, as they don't really need to if its a straight forward application.
but your right about the visit visa, it can be hit and miss, some filipina have got a visa with no job, savings or property and others have been refused who had property, a job/business etc
also because your g/f is not classed as a family member, if she is refused, she will have only limited grounds for appeal.
so get your app 100% water tight , look into the common reasons for refusal and address them, and keep your fingers crossed
