Once you have the proposals and comparisons you can then use the best price and service to negotiate with the others to match the offer. You will be surprised how a bit of competition can sharpen a provider’s pencil. You can then compare, contrast and further negotiate to match price and services. At this stage you can specify any additional requirements that you wish to vary.
It is also worth getting quotes from all for a fixed fee for a one year term and then asking what the cost savings would be for longer terms with 3 years being the maximum term. You can generally negotiate strata managers costs and services if they are keen for the job – but ethically you should only do so if you are comfortable that you will retain them for longer (unless there prove to be unworkable problems).