Most appliances in the home come with warranties already built into them. You should first read them and compare them to what you're being offered. You didn't mention if the appliances are new or used, and what the ages are of each one. It will make a difference.
The chances of a new appliance, or a relatively new one for that matter, having a problem in its 'early years' is slim. That's why the mfgr can afford to offer ones up front. Then, when they expire, you are offered extensions either from your source or directly from the mfgr if they know where to find you. It's a real crap shoot if you ask me (which you did kinda indirectly.) Refrigerators, washers, dryers, microwaves, TVs, ranges, dishwashers, and so on are fairly reliable. IF they weren't, they'd be out of business (and they're very competitive!) HVAC and HWH units are a bit 'touchy'. We depend on them much more, and are more apt to 'insure' them against failure.
Personally, I've been offered warranties of all kinds over the years for my appliances, and never took one (exception coming later.) The $$$ I saved is in the bank waiting for the appliance to fail so we can either fix it or replace it. The TV is 14 years old, refrigerator 6 years, dishwasher & stove, 8 years, microwave 14 years. Every year, we receive a solicitation from GE to have our refrigerator protected. THey want $79 per year!!! On the other hand, we have our HWH and HVAC units warrantied with our utility company. For $84 per year, NOT providing any maintenance for us, we warranty them. With a service contract, you're more likely to get someone out to your house right quick because you're already a customer. That's kinda how we want it (although it costs us.) Some would argue that this is unnecessary and that's OK. For us, we're happy.
Soooo, you need to weigh the +'s and -'s. W/O knowing more in your case, well, you can see what we decided. My best to ya and hope this helps.