On the subject of attachments - can UE4 do multiple attachments - without knowing how many 'potential' file fields your likely to need.
ie. Pretty cumbersome to make a form with 20 file fields - especially when a client decides they want to send 21 attachments.
I have a client who runs an accident repair shop
they send images of cars to insurers - that might be 1 shot - that might be 20?