Campground Wifi

I have the opportunity to setup a hotspot in a campground. Looking for suggestions to use for radios, I have 3 poles I can mount to, to provide decent coverage. Was going to mount the aps high enough to get above the bigger campers but low enough to stay under the tree canopy. My wisp is on the water tower which is about 600 yards and clear line of site so providing the backhaul will be easy. The tricky part is I am running epmp  2.4ghz on the tower for my wisp which I want to be sure I setup correctly so I don't interfere with my wisp signal. I need captive portal for weekend warriors at the campground it would be phone connections and for the seasonal sites I could install a client radio. Looking for some feedback on ap radios, and billing/hotspot software that I can billing on daily or weekend rate use with credit card. I was thinking about using 2 Force 300's for backhual to a Microtik router. Then I was going to use 3 cnpilot e501s in a triangluar mesh mode with cnmeastro handeling all captive portal and Credit card payments.

If I use mesh mode on the 5ghz side of the ap's can a client still connect to the 5ghz signal or is it strickly for backhaul at this point? 

I am running my wisp epmp 1000 gps sync in 10mhz at 2422 and 2257 a 4 sector config. Which only leaves me with 2437 to use for the campground in a 20 mhz config although I wish I could get 10mhz of space on each channel but I dont think I can. If I put the ap's In a triangular pattern I will probably self interfer any thoughts on this little project of mine??? 

Another thought I had was to only use the 5ghz as the AP side for the campground and use the 2.4 for mesh backhual. This option would be less stressful on my wisp tower. I would loose some older laptops from connecting but I should get all the phone, tablets etc... 

Thanks in advance. 

Thoughts???

Otherwise, could I power up some UBNT Iso station ac's from the other POE port on the cn e501s's and use the iso stations as the backhaul and forget about the meshing. This should give me much better max clients per ap.