My apologies if you think I am looking down on you; I'm not. To me, a few hundred dollars is also a big deal, but in terms of starting a business such an amount used as capital might not be sufficient (its all about the context).
Having an agreement dished out clearly in ink would protect you.
I am not quite sure about handing flyers door to door-I believe it should be fine. I receive such stuff at my doorstep very often these days too.
You may wish to consider advertising in online forums/directories like redad.com, singapore classifieds, singapore expats, gumtree.sg, olx.sg, mocca, hardware zone forums, VR zone, Kiasu parents forum (they have a marketplace there but you need to have a website). Most of them are free and it could help you reach out to a greater audience.
I am always actively looking to finance small ventures; if you are interested to consider me as an investor, feel free to drop me a line.
(Oh, if you are setting up a virtual blogshop, then make sure you build a nice website
that is user-friendly.)
All the best. Peace.