Yesterday, I went to... look at houses price houses window-shop for houses do some research on house prices scope out some houses check out house prices check out some properties (that were for sale)

I think that you're learning BrE. They have 'estate agents,' (which is what we Americans call real estate agents.) Hence the confusion. IMHO

In the US, an "estate sale" is when someone dies and their heirs sell all of their belongings. You would only say "I went to several estate sales" if you spent the day looking buying dead people's stuff. If you went to look at houses to see which one you wanted to buy, you would say "I went to look at houses" or "I went to several open houses." (An "open house" is when someone who wants to sell their house gives 3-4 hours for people to come and see their house.)