Passport america pays for itself quickly but we don't use it often as we would like.If you travel much( as opposed to month stays ) I wouldn't be without . Its valid mostly for 1-3 nights only and weeknights not weekends .. there are of course exceptions. Escapees membership is useful with 10 - 50 % discounts and the few member parks. and escapees has other valuable reasons to join for a full timer.
Thousand Trails has zone membership I would do first to see if they Fit your style. We did that with Two Zones but found that where we wanted to be, wasn't where they were, and a few were less than we expected, so we dropped them... something you can't do if you BUY a membership. try before you buy .. it may be a way to keep things cheap or it may not work for you. They have changed The Zone rules and Membership rules lately so review carefully.
We are also FMCA members needed for our rv brand club and Good Sam members (Just a bad habit I renew ) but they ea offer 10% off and almost any park will offer 10% to AARP VET GS FMCA etc.
Coast to Coast RPI etc we havent found a need for YMMV !
Good luck on your year to full time! We are starting our 4th year.