Property Tax Assessment Appeal in Washington DC - HELP

[Zee Ayezain]

Hi BP, 

I purchased a 3 unit multi-family property in Washington DC in mid October 2019 for 1,050,000 with 20K in seller credits. An identical property on the same row of row-houses sold a month after mine for $1,050,000. I recently received the property tax bill and a notice of proposed real property assessment for 2021. It has my 2020 assessment at $1,110,000 and my 2021 at $962,440. 

I have a number of questions:

1) Why would my 2021 assessment be lower than my 2020 assessment? Im not complaining but trying to understand.

2) Can I appeal the 2020 assessment or can I only appeal the 2021 one?

3) If I appeal the 2020 assessment, do I risk increasing my 2021 one?

4) Should I request an appeal to $1,030,000  since thats what I paid for it? 

Thanks,