I wanted ask you about the rent increase.

Not done yet.. you need to figure out the strength of the lease.. absolute/true NNN is the best.. years till expiry, how new the building and yearly increases impact how close to the market cap rate the building should be..

I am toying with the idea of trying to get into a real estate office as a realtor in order to increase my knowledge of how things work so I can pursue my goal of having 40 units.  

If you do purchase the property then you'll probably want to give the tenants a decent advanced notice of the intended rent increase so they aren't sticker shocked at renewal.

I have a 7 unit apartment complex that has a vacant 450 sq ft space between two existing units that I intend to convert into storage as a way to better serve tenants and force appreciation thru increased NOI.

My second thought is to do a separate refinance (no cash out), to a 30 year loan, lowering my monthly costs and increasing my cash flow. 

So if your plan has a high probability of success all the way out to age 100, then the probability only increases if you only live to 85 or 90.Also, with younger clients, I tell them to plan as if Social Security will not be there for them at all (note: I do believe it will be around for a long time, though it will likely look different 30 years from now than it does today, which may mean decreased benefits versus what you could expect if you retired tomorrow), and build a successful plan that way.

No increase in rent or change in lease or signed statement was imposed, just written text message communication. 

I would only consider doing this if rent increased to at least the market amount post renovation.  

I put them out day one and keep them out until they are rented or sold.I generally see an increase in traffic while it's up and I do receive phone calls looking for other properties, so it's working in some way.