Mini-split heat pump installation

I'm playing with the idea of installing a small mini-split heat-pump to heat/cool my home office and thereby avoid running the main central air system all day. I really only need to heat/cool about 125 of my 2500 sq ft most of the time.
~9000-10000 BTU units are available from Soleus and others for only around $500. However, installation is non-trivial. I'm not confident in my ability to handle to the electrical work to code and I'll clearly need an HVAC guy to charge the system.
I believe my main panel will handle the extra load and the cable runs from there to the inside and/or outside units would be fairly simple.
I'd appreciate any thoughts on what professional installation might cost. Or any other general comments on the wisdom of this whole proposal.
Finally, I'll need to build a small cement pad for the outside unit. This I could do myself to save money. Any thoughts on the design approach/spec? Those units weigh only 60-100 pounds.
| Malcolm Hoar "The more I practice, the luckier I get". |
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