And by scale, you can hold more money back knowing that some assets may need an injection from the cash flow of other assets.  

Three words: Asset Price Inflation.Remember all that money the Fed printed years back (Quantitative Easing) - simple economics tells us you cant inject this much money into a system without causing inflation, but consumer prices haven't moved much so what happened?

@Salvatore Lentini when you partner with passive investors, are you also injecting in equity, or do you strictly use their equity, giving them a larger share of the deal and you taking a smaller share?

Our plan now is to sell a single-family in our portfolio that I've never liked but is mostly paid off, and 1031 the money into the cash injection for a commercial loan by our regular banker.

Here in the states we produce medical consumables using plastic injection molding.

:@Matthew Forrest - With all due respect, your comment "The government injected trillions on dollars into the economy and those dollars are not just going to disappear.

Bear with me here:Raleigh population: 423,719 (local unemployment 3.6% = 407, 945 employed407,945 * $53,653 aver local salary = $21.9b total annual income of area50,000 AMZ jobs * 100,000 aver salary = $5b incremental annual income from AMZ$5b / $21.9b = 22.8% increase in annual income from AMZNow......I realize that not ALL of these 50,000 AMZ jobs will be injected into the Raleigh economy in one year, but if it takes two years, thats roughly an 11% increase and three years 7.6% (holding local area income stagnant over that time frame, which it wouldn't be)If you broaden the same calculations above to include all of Wake County, the numbers are obviously less impactful (8.5% annual increase in County-wide income in one year), but not immaterial IMO.Another simplistic way of looking at this is the average AMZ salary of $100k is almost twice that of the average Raleigh salary ($53k), so the argument could be made that that's almost like adding 7,500 jobs (as measured by purchasing power) to the local area.Again, I realize these are VERY simplistic arguments and it wouldn't take much to poke holes in it if you really want to parse it, but I do think it makes a solid case for it being a material impact on our local area here in RaleighThat said, I'm certainly not suggesting anyone invest here locally based on just that alone.

Or to Axel's point reinvest cash flow, so your houses have babies and the portfolio grows without further W2 injections from your heavily taxed paycheck.My point is to find the right balance between cash flow and equity, and that balance is different for everyone.

Could easily pay off entire loan balance or inject a large amount of equity in order to refinance and still make the deal work.- Puts material equity into the deal, in the form of cash. - 750+ credit score- Pays legal fee for seller to have representation from lawyer to walk them through the terms of the subject-to deal, including making it very clear that there are extremely real, and potentially devastating risks in the event of buyer default.Irresponsible/unethical Sub-to buyer looks like this:- Poor/no credit - Would not qualify for the mortgage they are taking over payments for, much less a new mortgage if a forced refinance event happens.- Is attempting to get 100 subject-to deals, but is not even capitalized to pay off or inject enough equity to refinance a single one of the acquired deals to have it qualify for refinance, much less a few dozen of them. 

I know you can convert a traditional IRA to Roth by just paying tax on the amount converted, but no other ways to inject more money in there.