Right now pre-built PCs are the cheap option, even for the RTX cards...
Or you have patience and wait it out. Which i didn't have so i bought my new PC for last Christmas and put it together myself - i checked price trackers on a daily basis back then and when the prices were at a level i was ok with ( GPU at about 20% above initial price was the highest markup) i placed the orders.
Since then the situation has gotten worse - either your pockets are deep enough to be able not to care or you'll have to wait quite a while for prices to stabilize at normal levels.