Is that the best way or should I use another process server?

This includes servers and real estate agents among others.

He agreed to let me use the software directly from their server so as not to have to buy it and to make it easier for them to answer questions about problems by  just opening my account.  

Our server delivers notice to "all other occupants known and unknown in possession of premises" while on site.I find it very unlikely a school is requiring the dependents to be on the lease... but we have had schools contact us to see if students lived at the claimed address.

I am 7 days out from closing and the current seller has not completed the eviction they started for one of the units because the tenant has been dodging the processing server.

Late fees, notice to pay or quit, evictions or towing of vehicles is a psychological source of leverage which only in the most server cases is actually applied.

With dedicated servers storing data the county number is limitless

It servers that purpose as we have never had a tenant get charged more than 1 time for lockout in the total duration of their rental and we have some long term tenants (we had one move out last year that we inherited that had total time in unit of 28 years - that is our record but we currently have two that are over 20 years).$150 for lockout is a fair rate for dropping things to let the tenant in. 

I will also send out the lease termination notices using either process server or certified mail.

Companies like Amazon have invested quite a bit of money into warehouse space in and around Des Moines for server farms.