If you have in the past few years purchased equipment with own funds and you would now need the liquidity you can monetize these assets via a Sale & Lease back structure. Just sell the assets on book value to a Leasing company and lease back the equipment over the next few years. Besides gaining immediate additional liquidity you can also have tax incentives as lease payments are OPEX and fully tax deductable - so you can shorten the depreciation time and reduce your tax burden (for details please consult with your tax advisor).
For further information please have a look at the GERMAN DESK BROCHURE which provides some indicative interest rates and what is required by the Leasing company to check your bankability.
Feel free to contact me for additinal discussions: firstname.lastname@example.org