Forget about quadrilateral as it will ruin your recovery rate and will get you disabled for years.
Regarding LON femur, it's not a good idea indeed but doable if and only if you stop at between 5-6 cm mark. ROM will still be limited but it will recover much quickly compared with 8-10 cm most guys do in Turkey with LON femur.
Tibia can be done for 4-4.5 cm with external only with decent orthopedic surgeon who knows how to manipulate the external frames and make the bones as straight as possible before consolidation phase. 4-4.5 cm will take at worst 9 months and at best 4-5 months in frames so it's definitely worth it when doing that low amount because you get rid of nailing insertion and removal surgeries in that case which is additional cost, invasiveness and risks, especially for tibia.
IMO, if you are ok with 5.5 cm femur, you can do LON with to save the costs, but only with reputable doc who will monitor your case closely and will treat you promptly if difficulties arise in the process. Disadvantages are ugly scars and limited ROM but with 5.5 cm, ROM will return quickly and scars can be dealt later. It will be much cheaper than doing Precice but with added risks like infections for example. But, 5.5 cm on femur won't shift your mech axis to a same degree if you do 8 cm for example so you will not get deformed legs which is another plus stopping at that range.
IMO, first do femur for 5.5 cm which will take exactly 2 months, then recover for another 2 months in order to get the sufficient ROM back and then go and break the tibia with fully external frames for 4.5 cm which will take between 5-9 months in frames. This is the most realistic goal for someone on tight budget and who wants to lengthen proportionally and get solid 10 cm height. Rather than maxing out femur at 8 or 9 cm, it's way safer doing 5.5 / 4.5 split in terms of risks, recovery and final gains / aesthetic results. The only downside is more time and money is needed but not that much for it to not worth it.