Consumer Reports (https://www.consumerreports.org/join - $10/month digital) has ratings of washer/dryer pairs. You can find pairs within your price range and then limit your washer search to stackable models. I've found that following up with owners' reviews on sites such as Home Depot Best Buy can be very helpful in pointing out features and deficiencies that may only be noticeable with long-term use. Be sure to read the installation manual or specs to make sure the appliances will fit -- some are enormous -- and your house meets the requirements. Reading user guides helps in selection. AJ Madison sells many stackable sets.

There is no shame in admitting that you "don't know what we need or might need" when buying a new washer and dryer. Getting up to speed on current tech is just as tough as buying a car or doing graduate level research..

wdccruise has given you a start on models to check out by suggesting looking at Consumer Reports and downloading PDFs of the user guides and installation instructions.

When you don't know what you are looking for yet, you might might find it helpful to check out the Wirecutter article "The Best Washing Machines (and Their Matching Dryers" if you have not already seen it. That article was updated a month or so ago. It will at least give you a start on winnowing through the bewildering array of choices, features and marketing gibberish.

FWIW, both CR and Wirecutter give high marks to LG's relatiively new WM3900 model for cleaning ability, relatively speedy cycles (for a front loader), high efficiency. and likely durability.

If that model is in your budget, you could search the threads here for discussions of it (we've had several in the last few months) and also check out the automaticwasher site where laundryphiles hang out.

My friend has had an Electrolux 627 stacking set for about five year and loves it. She has had no problems with it, and says it cleans better than any washer she has ever had.

Do you need a stackable unit? The reason I ask is that all the front loaders have some degree of mold build up. You need to dry the gasket out after each wash and leave the door open, in addition to the detergent dispenser. I've had an Elecrtolux front loader pair (very good reviews mentioned above). Kids are gone and it's just 2 of us. I will have had them for 6 years in July - They've been repaired 4 times. I'll be doing a remodel in the near future and I am going back to a top loader from Speed Queen. They are the most like the old Maytags that we had for 20 years or so. Another thing to think about is that in order to get the clothes out of the washer, you need to bend down, no matter how careful I am stuff always ends up on the floor when trying to get it into the washer.

Mold can be an issue in ANY washer, top or front loading.

I second the recommendation of the LG 3900. It cleans and rinses fantastically, finishing most loads in about 30-40 minutes. This washer is rated #1 by Consumer Reports and the Wirecutter.

When I had to replace my washer/dryer (that lasted over 35 years !!!) I researched a lot of models. Speed Queen was our choice. They also make stacked models. American Made.

I asked the installers about other models they deliver and repair. They told me that if LG is on the order, they give the job "to the other guy" because parts are difficult to obtain and the machines just don't last.

I know Consumer Reports likes LG but I don't.

I purchased an LG French door refrigerator when we moved into our home. It had a 90 day warranty. About day 95 I had trouble with it. (Fridge part froze items, freezer thawed them, among other problems.) I don't usually purchase an extended warranty but we did for this refrigerator. Glad we did because it took a full year of almost monthly service calls before the company agreed to replaced the unit. I asked for cash so I could buy GE.