Regarding those pesky account limits at BetMGM, please, do not fret! I mean, if you happen to snag a slightly larger profit on a single match—say, upwards of 800 dollars—you might want to prepare yourselves for the possibility of your account being limited to a profit range of somewhere between 6 and 36 dollars per bet, depending entirely on which sport you are eyeing. But until that happens, you are perfectly safe! This is especially true if you steer clear of those niche markets like USTA matches or smaller regional basketball and volleyball leagues.
So, here are a few of my own personal reviews regarding the various sportsbooks I have utilized or experimented with over the years:
DraftKings - (perfect for all the "standard" sports). Their limits are absolutely fantastic! You can practically wager whatever your heart desires on a single outcome. Typically, you'll see limits starting around 500 dollars for the smaller sports, scaling up to a whopping 40,000 dollars for major American sports. If you decide to drop 500 dollars on a specific play, they will simply adjust the odds or the margin accordingly, allowing you to place more money right then and there, almost indefinitely! The only real downside is that their market depth for things like moneyline, totals, or spreads is a bit thin across all sports. They do offer corner bets for the big leagues, though. A MASSIVE DRAWBACK when betting on player props (for instance, the NBA only features player props during the playoffs, if I recall correctly) is that the player MUST actually start the game for your bet to be valid.
BetMGM - truly the gold standard for live betting offerings! However, if you hit it big on a single match—think USTA tennis or some obscure regional basketball or volleyball—do brace yourselves, as they might limit you to a 6 to 36 dollar profit window, depending on whether you are playing tennis or the English Premier League. Before the match kicks off, the limits vary wildly by market: you might see 80 dollars for USTA, 160 for handball in minor leagues, maybe 300 to 360 for handball and basketball, climbing to 1200 for the top-tier leagues, and reaching as high as 3600 for major American sports. Generally speaking, those limits are about 4x or 5x higher during live action, though they fluctuate based on whether you are betting the match itself or specific prop markets (where limits tend to be a bit tighter).
FanDuel - they have that Asian sportsbook feel; the limits are quite decent, and they actually offer a broader selection than DraftKings—for example, they have HT/FT options which you won't find at DraftKings.
Dafabet - I suspect they are actually part of the same parent company as FanDuel, so if your limit is 500 dollars at FanDuel, you could theoretically put 400 dollars on both sides without the odds dropping too much. Just keep in mind that as soon as you approach that "max bet" threshold, the odds will immediately begin to shift.
18bet - a similar situation, except they can be incredibly difficult to deal with! They love nothing more than voiding bets if the margin shifts significantly. For instance, if you bet on American basketball at a -6.5 spread and it moves to -7, and eventually ends up at -23.5, they might just declare your bets void, claiming you placed them at an incorrect price and margin. On the bright side, they are quite good for Asian handicap soccer betting, as they allow much higher stakes—around 1,000 dollars for major leagues and roughly 400 dollars for those smaller, local matchups.
William Hill - they are quite generous initially, allowing single bets of 200 to 300 dollars pre-match and even up to 1200 dollars live without any fuss. Eventually, they might scale back your pre-match singles to around 35 or 40 dollars, but they still permit fairly substantial amounts during live play.
DraftKings - they boast a very wide array of player props (especially in basketball). The catch is that you really should keep your wagers under 25 or 30 dollars if you want to avoid being flagged and limited. Interestingly, the owner of the book is Tony G (the poker player, who, if I am not mistaken, was recently involved in running for a seat in the US Congress, or perhaps just considered it—I cannot be entirely certain!).
Tipico - they don't accept players from America, but if you could somehow get access, I would actually recommend them; they are known to allow 200 to 300 dollars on singles and are notoriously slow to adjust their odds.
Whatever you do, please stay far away from the following books:
betway, bet2be, betvictor, betcity, marathon, FanDuel, betsafe, betsson, betclic, expekt, tempobet, titanbet, and winner.

Here are the current limits for the Champions League. So, that figure you see above, 61,712.00, represents the current "max bet" for one of the handicaps. It isn't actually that high right now because of the red circle icon indicating reduced limits, but as the match approaches its start time, the limit will either reach what is written above (when the circle disappears) or potentially even higher (indicated by a blue circle).