Spid,
Trust us on here... In this climate it is better to walk away with a loss of however much versus complete all of the additional training and leave with an even bigger loss when you realise the industry at the other end isn't any where close to what it was. If you can, delay your training until things pick up again as you'll stand more of a firm chance then. I have had friends and acquaintances who have lose their jobs in the past few weeks. I have managed to hang on to mine but only just - literally by the skin of my teeth I reckon. The industry is so bleak.
Can I just ask, where are you training and why did they not explain the expected costs to you prior to you signing up? This is all stuff you should've ideally been told about or advised of. In trying to give you a clearer answer though:
1. Annual Medical Costs (increase upwards to £500+ depending on what is due each year).
2. IR revalidation costs (alternates bi-annual between sim revalidation and real aircraft reval/renewal).
3. Interview costs (presuming there are any jobs going) are anywhere from £0-500 per interview depending on which airline and whether you need to account for accomodation.
4. Type Rating - You need the IR current to do one in the first place, least not a medical, and they can vary in cost too. To give you an idea the typical cost for a newbie to get a TR is around £20-30,000 for the big low-costs in Europe.
In this particular climate you're going to be lucky to find an airline paying anything for you, especially when there will be surplus excess crew out there willing. As others have also alluded to, keeping current is vital. Many airlines want 'x' amount of hours within the past few months at the point of you applying. If things recover in say 2023 a graduate in 2023 will be far more likely to get an interview than one graduating in 2021 without any additional flying hours since graduation. Just food for though.