For C41, you can get away with a couple of degrees of variation. Get a big tub of water (like, 20L, a big sinkful) up to 40C, stick a thermometer and your chemistry bottles in there, and then go to town with the paterson when it hits 38C. It'll be fine. For E6, not so much - you can and often will get lucky, but you can also produce sub-par slides. The variations don't matter in C41 because you can correct density and colour while printing, but slides have no such opportunity for corrections.
If you browse craigslist etc, you can often find cheap Jobos. You're next to NYC FFS, it's not like you're stuck out in Australia or something!