If you have a lower budget, try to find people who would be willing to partner with you on the first deal (or couple).

But to start off, I'd like to find a 3 or 4 plex, value add, House Hack in Chicago at $800k or lower but can appraise at 20% higher.

There are many options online that can help you calculate your ROI, but the formula is relatively simple:Total Cost to Invest (purchase price + rehab + any holding costs + commissions and closing costs on both sides of the transaction)Net Profit (sales price - total cost)Formula: Net profit / Total Cost = ROI %Also, not sure if you would like access to a spread sheet/calculator that can do this for you, but I have created my own. 

It was a second home from a family and I was able to negotiate lower.

Negotiation is a critical skill in real estate transactions.

Heloc is generally 10 or 15 years amortization verus a 30 year mortgage with the lower payment. 

It also usually comes with the bonus of lowering their monthly expenses over what they were paying in rent, but immediate cash flow is not always possible given the purchase prices in the areas most of my clients want to buy.

I stumbled on some information about short term rental tax benefits as it pertains to lowering W-2 Income. 

Make your offer a little lower because of it.

Assuming I can get financing, should my strategy be to lower my offer price and cover the reno myself?