Making offer on first property, a 4-plex. Anything I'm missing?

[Jonathan Cook]

Sold my house and looking to house hack. Found a 4-plex (2bed/1 bath ea). 3 are rented at average of $550/mo and I will live in the 4th which is newly remodeled. Asking 150k but has multiple offers. Planning to offer 160k. I have 20% to put down but would rather not if I can avoid it. Numbers are 

Price: 160k

20% down: 32k

mortgage: $575/mo

tax/insur: $230/mo

total: $810/mo

rental income: $2250 (including 4th unit)

thoughts?