No cheap way
Usually the least complicated is the cheapest in the long run, tugging gliders may tot up the hours but it will do nothing for your navigation skills.
LAA types are a better option until a big bill turns up.
If you rent you will pay more but any technical problems are not yours.
The best value is probably a good rental deal that will let you do a lot of navigation well away from base. This will hone your skills for the (f)ATPL skills test and save you money on navigation training.