In the past I have usually held only one client at a time, in 2019 it is my hope to grow and take on multiple clients in order to make this side job a career.

I have multiple investor and realtor clients that I help with projects.

Yes I don't think I would get a good start using my 15k, but it could be use by multiple partners to purchase a single or multiple family homes flip since its quick.

Based on your comments above, it looks to me that you are advocating for bad service for everyone but the multiple property owners. 

Obviously a big part of investing is working with different lenders and each one needs to run your credit (sometimes multiple time) in order to approve you for loans.

If you are still looking for a multiple, house hacking may be a good alternative.  

Out of all the properties I've owned I've never been the "landlord"...it's really a technical term that has stuck around for some reason...anyway, my position is always that I work for the company that owns the property...even though it's my sole or multiple member LLC...there's nothing wrong with holding property in your personal name...an LLC really doesn't offer that much protection anyway...I guess the point is to consider transferring title to your LLC...though there are some things to be aware of here. 

It also clears any misunderstanding about who pays what.When you have multiple tenants with different type of leases to deal with, you quickly realize that the more uniform your leases are, the easier is to manage your tenants.

If you had multiple renovations to make at once that would be a larger expense and difficult to save up for then a HELOC might make sense.

I sometimes discount the pet rent for multiple pets.