I would try expired domains - the.domain.name is a great site to grab expired domains as they come up every day. It does searches on keywords so can find valuable industries related domains. Low fees and can get a website created for them - they rebuild the old site so you can redirect the pages to a new designed website.

I know a lot of affiliate marketers - and am one myself. There are numerous affiliate conferences where you could find people to help. What exactly do you need? Are you looking to set up an affiliate program on one of the platforms like CJ or ShareaSale? You can email me at aussiewebmaster@gmail.com to discuss.

I would go with subdomains unless you are using the same content across the various countries as it applies - don't want duplicate content issues. Also use hreflang for languages and regions https://support.google.com/webmasters/answer/189077?hl=en

try taking pictures of your clients when done and post to your Facebook page - get their FB info and tag the photo with their name - they get notified and share and all their friends see it