Pretty easy to sum up for you the major ones members are using. I recommend to avoid Trifexis and Comfortis because of increased side effects:
Oral route: Heartworm prevention: Ivermectin or Milbemycin ( various brandnames )- can probably stretch out dosing to every 6-8 weeks if you know for sure dog didn't throw up
Flea and tick prevention: Nexgard (monthly) or Bravecto (every 2-3 months)
Topical route: Heartworm prevention: Revolution or Advantage Multi monthly (these also take care of fleas)
Flea and Tick Prevention: Vectra 3D or K9 Advantix II monthly(advantage of these two is they have permethrin to prevent fleas and ticks from approaching dog but is toxic to cat for 48hr).
Some people use Seresto collar which can last for up to 8 months, doesn't seem very commonly used in our group.