Onomo hotel was good, I'd recommend it. We went to the airport for a "dry-run" the day before departure to figure out where all the different offices were to pay fees, file flight plans and so on, like much of Africa it's not at all obvious to the newcomer. Fees were very reasonable.
Best to use Jetex flight support in Africa. Saves not only massive of time but works out cheaper because the locals know it is not worth scamming Jetex. If they park the fuel truck in front of your plane and refuse to move until you offer "something for the boys" then you just call Jetex and it is sorted pronto.