Is trading a USD base pair cheaper?

I’ve noticed in paper trading that when trading a pair where a foreign currency (at $1.30 rate for example) is the base and USD is the quote, I never end up with the 50:1 leverage because I’m not paying $2,000 for 1 lot, I’m paying anywhere from $2,300-2,700 for a lot. I can’t seem to wrap my head around this - but does this even out for me down the line, or is it smarter to trade pairs with USD as the base so that I’m not using up as much margin on a trade?

I think i didn’t get your question properly but as far as i have understood Use this calculator to calculate the price of pip in each trade,because the value of pip depends upon the Currency pair:
Pip Value Calculator, Pip Calculator, Pip Value Information

Your margin requirement is based on the value of your position, not the units. If you trade a USD-base pair the units will be the same as the value, so the math is easy. When you trade a non-USD-base pair, like EUR/USD, the value of the position is calculated using the number of units of the base currency. So in the case of EUR/USD, the units are in euro, so the value of the trade is Units x EUR/USD. You’re still on the same leverage. It’s just that with EUR/USD the value of the position is larger so you have to put up more margin.