If the seller is not cooperating, I suspect something's going on.All wholesale deals require that you first establish a rapport with the seller. 

You'd have to establish a complete team there first, then find the properties to fit this scenario, then...all remotely.  

The biggest thing is to get started and get established so that when the market changes and there are great deals everywhere you are ready to take advantage.

Regarding property management fees, I would estimate about 9-10% of rent plus a tenant placement fee for a well-established company.

If you can establish a good relationship, they may even send referrals your way when you're ready to develop the park.

Once established in these deals did that income provide a baseline to become an investor? 

I wouldn’t do the extension just yet wait to get that property established the way it is first then maybe down the line do it.

I do not have an established relationship with a contractor I trust and this is the missing piece to my puzzle and if I really had to I could do the work myself, so I feel this will allow me to not feel pressured into making a bad decision. 

As I am interested in keeping long term established good paying tenants even if I leave a little meat on the bone...

If you are looking for a traditional turnkey company (one that buys, rehabs, rents, manages, then sells the property to an end investor), there are no established companies that do that.