Second hand kingsong S18 and S16 Pro

[HappyDave]

First of all, some context: I am a beginner, have 15 hours of practice, just learned how to u-turn and recently I have made a short ride around big park. I have been learning with v8f and v11f models. My end goal for EUC would be commute (10km one way), ride around the city and maybe do some low off-road/tricks.
 

My initial plan was buying an A2, practice with it while waiting for S16 Pro gets improved/problems are fixed with following batches. I just wanted to avoid buying a first batch wheel, but at the same time I wanted some EUC for practice, improve and play around so that's why I bought the A2.
 

Just after buying the A2 the other day, I have found a second hand kingsong S18 for about 1000 dollars with 70km. So now I am tempted to buy the second hand S18 and resell it when S16 Pro problems are solved and new batches are released. What do you think?
 

I feel like buying the S18 would be a waste of money since I have already ordered the A2 (it will take like 1 month to arrive), but buying the S18 now will allow me to have an EUC for practice without having to wait a month, and also will allow me to practice together with my wife with A2 and S18.