Amount of money to invest for a game ads - 500$? 1000$? 5000$?

How much money should I invest in my game? Is racing / arcade game. It is in english and also fully translated to polish. This game is quite good ( spend 2 months on it with fellow artist). I was thinking about buying some installs in poland since it is already translated.
Therefore I have few questions for more advanced users:
1.Where can I get stats on how much downloads I need to be featured in given category in given country? (for example 50+ in racing - poland)
2.Which ad network do you recommend and what is the REASONABLE amount of money I should invest?
3.How risky it is? Are there actually people putting money in ads and still not getting their money back?

1, You can try Appbrain, they offer Pay per install, it’ about 0.8$.
2, You can pay as much as you can but depend on your game, if you think it good.
3, Very risk. There are many games nowadays. I pent more than 1k$ for a game and receive back only 100$.

idk if u used appbrain for promoting in poland but the lowest cpi is 0.2$. i liked it cause i got lot of quality instals. but still consider the risk, its not like u gonna get money back from every app. u wont get 100% money back from only bought installs so u have to make a long term plan how to get organic ones.
i heard that u can get lower cpi from fb campaign but havent used it.

i got 30% money i put in my apps (for now)

$0, why? Google have now uninstall rate in ranking algorithm and you can only destroy your position or generate filter for months, DON"T use CPI, only normal ads

Why CPI generates more uninstalls than PPI?

probably they also see how many times user launches the app after installing it. superb google.
incentive based installs should be avoided. But don’t know why ramizxp advised to avoid CPI campaigns

CPI campaigns are better than other type of campaigns It will give your app or game a good boost. If you are afraid of getting so many uninstalls than try to spend money on a good quality app which users will love rather than spending it on a crap app. You are gonna get huge uninstalls even with organic installs if people dont like your app. Don’t try to spam your users with ads once you reach a good number of installs than enable ads and also fix all the bugs before running the campaign.

I have about 50% uninstall rate with appbrain its not bad cause theyre not incentives. just avoid incentives