Guess I just missed this thread as it was started a few months before we started the home buying process. We just bought our first house at the beginning of May. It wasn't the most fun process, but feel like we learned a ton and did really well. Between both of our parents and my brother being very experienced and knowledgeable on the process and a pretty good agent, we're happy with how things went.
Obviously down payment % is case by case person. I would not say 'you have to have 20% or don't buy'. But if you can find a way to come up with it without hurting yourself, it's clearly the way to go. My brother's advice for if you think you were going to be under 20% would be to find a loan for the difference that might be a higher interest rate, but it ends up being better than PMI which sometimes can cause you trouble down the road when you go to have your loan company remove it. It wouldn't have worked out for us but again, everyone's situations are different.
My best advice is to not get too attached to any one home and be ready to always be looking out for the next option, and don't be afraid to play some freakin hardball! That was the most fun out of it. Our house appraised significantly less than the agreed upon price so then we said that's the amount we were going to pay. Seller and her agent didn't agree and said they'd put it back on the market. We said okay, good luck. Then they agreed to meet us in the middle or something. We said no dice. Then she caved.
Then there was an issue of getting something repaired for like $3,000 or something that we weren't going to give in on. The selling agent told us the seller thought she'd already done enough and with how much interest there was on the house, she, again, was ready to relist. At this point, we were like 90% sure that this seller had already started the process buying her new house and even had a moving date. We felt our agent was on our side for sure, but just to drive the point home, I looked up several other houses we liked and told her to tell the seller's agent to suck it and here are some other houses we'd like to go look at this weekend. That kind of thing can definitely light a fire under a selling agent who, along with the listing agent, just want to get the sale done and get their cut. We got a call a day or two later that the repair was going to be made. My fiancee hated the emotional rollercoaster, which it definitely was, but I was like c'mon! It's like we just won a $3k hand of poker!