Cool, so few survivors?
For me fuel hasn't really been an issue since the very start, running a quite small regional operation out of RIX my main problems were at the startup phase (getting enough plane while maintaining profitability). Also I pretty soon decided on a fleet strategy and which planes I would get, and with that knowledge I could save up money so that I could own at least 50% of my planes from each new order (of course buying the non-owned ones up when more money came in). When I got bored and was rich I opened two smaller bases, and to keep the game fun until the very end I opened a base in Bucharest and bought Mitshubishi Regional Jets just for fun (my 4th fleet group).
What I think helped me greatly was also the choice of An-140 as a turboprop. Sure, the Dash8-400 or Saab2000 might have been a slightly better choice from a speed/fuel efficiency point of view, but An-140's never had a long waiting time and I could get them whenever I needed. And now, with production lines closed, there are quite a lot of them on the used market if I need some more planes for smaller routes. I think I currently own something like 60-65% of all An-140's built (i own 80+ of these small props).