Maybe not what you want to hear but you should really go and discuss your plans with a local accountant. Keeping proper records for a business which hires out equipment and, presumably takes refundable deposits, and probably sells consumables, is not straightforward. If you don't get your record keeping right from the beginning, it can result in all sorts of problems in the future. I had the task of sorting out a mess for someone doing something similar several years ago. It cost them considerably more for us to sort out the incomplete records than it would have done if they'd come to us at the beginning and allowed us to set up a decent record keeping system.
Unless you have set up as a Ltd company, you are not a director so cannot have a director loan account. You may have a drawings account.
The treatment of the items you have purchased will depend on what they are, what they cost, whether or not you have used them.
You say "stock" but is what you have purchased really assets to be used in the business and hired out, or is it a mixture?
Normally for assets/stock introduced into a sole trader business we would take a view about the value at the date of commencement, allowing for depreciation since the original purchase date. However, if you have started buying items with the intent to use them in your new business and they haven't been used for anything else, a higher valuation might be used.
As I said, the treatment might vary depending on what the item actually is.