I'll be brewing for my second time in Paraguay and have a quick question in regards to the summer conditions down here. How important is it to maintain the fermentation yeast temperature range after primary fermentation? My main issue here is the heat (I live in a small hut with no AC). Also when it comes to bottling, if it's in the high 80s will that simply equate to a faster carbonation time or it may also potentially have negative effects?
It could be OK, the majority of flavour compounds form in the first three days of primary.
You will almost certainly get faster carbonation, and you may get a slightly more ester rich aroma but I think you should be fine. I bottle in summer in the UK around 25C/77F and I get good carbonation and no ill effects. I conduct primary at 17C to 20C in the cellar, but bottles get stacked up in the kitchen.
You might also consider brewing beverages that are ok to brew in warm temperatures, i.e mead. I've had great results with mead at 75°F, using Lalvin wine yeast for white wines, especially Prise de Mousse, the champagne yeast. Plus, you probably have unique honey available to you there.
A suggestion I got from a home brewer when I was concerned about heat (not as high as yours) was to drape an old t shirt around my carboy and keep the bottom of the shirt in a bucket of water. The capillary action wets the shirt and evaporation will cool things down. Not an accurate way to control temperature but it should be somewhat cooler.