I fight humidity here and all of it’s attendant problems like mildew and bud rot. My advice is to get the largest capacity you can afford because you can always turn it down. A large reservoir is good too to avoid it filling to capacity and shutting off. I got one with an optional drain hose which I then dump into a Homer and reuse.
I try to get mine down around 35% with good airflow in late flower. I also only run when the lights are out. Heat can be an issue so FYI.
@Myfriendis410 Fortunately I have the ac vent hose routed to the tent in a spare bedroom. But cant run ac 24/7 yet, plus with lights and fans off it gets humid as well as when ac is off (when the wifey gets cold lol). plus i have to get lower than 50% RH soon which is the lowest it goes with AC on. I think that midsize one with RH control i posted earlier will do the job. At least I hope.
@Countryboyjvd1971 is an HVAC expert and IIRC he suggests you cool the room that the tent is in as opposed to directly into the tent; better control. Dehumidifiers only work if you don’t have to remove a lot of air either so keep that in mind. If you have a big exhaust fan it will keep your RH high. Which militates towards a larger unit.
@Myfriendis410, @Countryboyjvd1971 actually helped me set up my AC/Exhaust system. I have perfect negative pressure in the tent because of his help. The dehumidifier is just for when the AC is off for a few hours in the day and to take the edge off the RH to get it down to 30%. I wouldn’t have been able to set up my system without him. 
@ThcinKC I finally ordered the ebay dehumidifier this morning. Will come sometime next week. I’ll keep up and show how it turns out.
@Botcan @ThcinKC @Myfriendis410 @Wildwest @dbrn32
http://imgur.com/a/0MdKu2d@Countryboyjvd1971
Heres an update. Dehumidifier is working like a charm. Finally entered flowering and she looks happy even after clipping a few larger fan leaves.
Awesome keep up the good work
She is looking beautiful 
excellent stuff, now the waiting game…i swear time slows down when you hit bloom 
@Wildwest I have definitely learned patience lol It’ll be worth the wait.
I thought i had all the patience in the world buuuuut im telling you man it wears thin towards the end!
Some have it, some dont 
I’d rather put 20 aside “just in case” instead of being too eager. It happens when it happens. I would be lying though if I said there hasn"t been a “just in case” in the past 5 weeks.
Looking good @Chip_Butterfield
Tbis is the fun part watching those buds stack up