How do you finance a big deal?

Up until this point my sweet spot has been 4 unit townhouses that I’ve financed with 20% Down from big banks (Wells Fargo mostly) on average I pay about 200k per property. I have several buildings all spread out and would like to move on to a bigger deal. I’ve found a deal I’m drooling over. The asking price and appraisal is 2.5 million but The seller told me he’d sell it for 2.2. Is there a way to finance something like this with 10% of my own cash or get the capital in a different way like asking the seller for down payment assistance? Is that a red flag for lenders? It’s a 47 unit building that is fully leased and stabilized. I just don’t know how people finance big deals unless the only answer is they have big money.