Account Fees - A company must charge fees for their business to remain operational , however you shouldn't have to pay extra for expediting investments, transferring funds, conversions, etc. 

Again... some of these extra expenses are mitigated if you owner-occupy. $3000 for closing costs seems low.

We just paid $1,100 for plan review and $1,600 for permit

I checked on the town code and the type of zoning it has is capable of having the dwelling changed from a single family into a dual family through a building permit process.

Just need the proper tradesman licensed in order to pull permits.

I can deploy 5 figures per month extra against the next crummy commercial loan I have over 6% if I want to, or invest elsewhere.

If a structural permit is needed you can't get one without an engineer report.

No deals, no extra payments (because you haven't used the line).You only want to increase your debt in a primary residence in two cases. 1) You make more money than it costs you.

One thing to note is that most DST’s are loaded with a ton of extra fees (sales commissions, etc), so they may not make such a great first option.

ARM loans, unless you pay a ton extra every month so that when it adjusts its not a shock, I would stay away.